I feel like I need to refute many pro-ban arguments, and elaborate on why keeping Gene for now is the right move.
1) "Genesect is overcentralizing because you need to specifically prepare for it" - You also had to use a Keldeo or Bisharp check/counter on every ORAS team, but no one's saying they're broken.
2) "Genesect is overcentralizing because there's no reason not to use it on every team" - I'm pretty sure Lando-T has more usage and things like Lati and Lando in ORAS still probably had more usage than Gene now. Usage aside, adding a Genesect can stack weaknesses and using a certain set can leave you weak to some styles, so it can't mindlessly be slapped onto a team.
3) "Genesect lacks full counters" - Well, there's also no full counters to Kyurem-B. Obviously Gene is a better pokemon but a lack of counters alone doesn't break something. You can still pivot around these mons reasonably well and revenge kill easily.
4) "Genesect is too versatile with its coverage options" - XY Greninja had coverage to beat like any possible switchin besides Clef and Chansey (taunt aside). Greninja's Protean boost is basically equivalent to a download boost (which is less reliable). Even Greninja now has few full counters if any, with even more coverage than Gene, so this doesn't make something broken.
5) "Genesect may have some walls, but it can just U-turn on them" - Any U-turn pokemon can use the move on any of its counters. Scizor using U-turn on Heatran isn't exactly a broken thing and this has more to do with U-turn as a whole rather than Genesect.
So, why exactly are people saying Gene is broken? As
Finchinator said, it's something like "Similarly to Hoopa, Genesect is very tough to switch into, but it doesn't have a crippling weakness like other good breakers." What this sounds like to me is that Genesect is just a good pokemon. It may not be super frail or slow, but there is always a trade-off in using a certain Genesect set. You also aren't necessarily advantaged for using a Gene while your opponent does not.
Generally speaking, we should really only be banning pokemon that warp the tier significantly or truly are too powerful. Something like Zygarde-Complete was just too good for OU, and Aegislash definitely had a negative effect on the tier that Genesect cannot even barely compare to. In the case of Lando-I, the quickban was less clear and maybe shouldn't have happened but the council was unanimous due to its Gene-like coverage + insane power simultaneously. If we just dropped Genesect into ORAS and went by this tiering philosophy, then hell yea it would be broken. But right now we have a new Generation that is still evolving.
From this point onwards, with this test included, we need to give the meta time to settle. As we saw with Pheromosa, many people (myself included) saw it as quickban worthy early on but eventually realized it can be managed. Pheromosa's counters like Toxapex can't be used on every team, but you can still pivot into it reasonably well and revenge it even without the hard counters. Additionally, many people thought Mega Metagross was broken, but later realized it can be managed. Perhaps the same will happen with Genesect, and it won't be seen as this menacing down the road. To ban Gene at this time simply stunts the growth of the tier, as
Jukain pointed out.
To suspect ANYTHING this early on is foolish. Something is either quickban worthy or it shouldn't be touched at all. Suspect tests exist to test how a metagame is with/without a given suspect. This point is rendered useless when a metagame has existed for such a short amount of time. Having a suspect test so early on was a mistake, but we can prevent consequences from this mistake by voting to not ban. If Gene turns out to still be an issue in the future, we can suspect again. Mega Sableye stayed in ou after its first test and was later banned, so please do not rush this decision and harm the tier permanently.
I'd like to respond in brief to some of these points here.
1) Genesect differs from Keldeo and Bisharp in that you need multiple checks to fully account for it. Many top tier mons have had ways around their checks before, but Genesect does so by having almost half a dozen comparably viable sets, rather than something like Latios running EQ for Heatran (which sacrificed Defog, Recover, or another coverage move). If a team is particularly inhibited by one Genesect set's check, it's not a strenuous endeavor to shift your Genesect to a different build to reduce that weakness. Genesect is not something that, even focusing specifically on it, can be properly handled by one slot on the opposing team. Having to dedicate not just one, but 2-3 slots to Genesect as a full Pokemon, an amount reserved for cores, is at least bordering on unreasonable to me.
2. Genesect isn't stupid to the point of "literally throw a set on your team with no observation", but for most teams that use offense and/or pivoting, it's very hard to find a team of this nature that doesn't see a low-cost Gain from using some Genesect set. It's not quite "no reason not to always use it" levels, but Landorus-I never reached #1 level usage and I doubt anyone will argue the presence he had one offensive teams and in the metagame at large.
3. Lacking full counters is not necessarily a cause for ban, but in combination with the other things Genesect brings, it's a severe issue to consider. Genesect doesn't even have a consistent check given the options it has available, with Fire types preyed on by HP Ground or Douse Drive, Toxapex by Thunderbolt, Bulky Dragons Ice, Steel types by Flamethrower, and that's just concerning coverage. Genesect can circumvent offensive answers using Priority, he has set up options in Shift Gear/Rock Polish, and there's bound to be other things he could dip into should the game call for it. These moves all give Genesect a large number of sets that make him all but impossible to mitigate/check, much less counter, in a single slot, but what pushes him over the edge is that Genesect doesn't forfeit momentum to most other forms of counterplay. Kyurem-B becomes a momentum drain after netting a KO since its speed and mixed bag defensive typing makes it susceptible to Revenge Killing, and it has to make every entry count because it's very hazard weak. Genesect, on the other hand, U-Turn out of most scenarios, good or bad, without costing the team pressure or momentum for doing do, and it's hard to discourage from leaving since it's SR neutral while also being immune to Toxic/Toxic Spikes and Sandstorm, meaning some decently common forms of wear and tear wouldn't work even if he does stay on the field. U-Turn prevents trapping as an option, and Genesect almost always puts the result in the user's favor based on the reactionary play he forces.
1. Genesect stays, opponent stays, Opponent is hit hard and possibly down a mon (Genesect advantage)
2. Genesect stays, opponent switches, opponent survived a Genesect turn (assuming he doesn't have an option for the new entry) (Opponent advantage usually)
3. Genesect U-Turns, opponent switches, momentum swings to Genesect with switch response (Genesect advantage)
4. Genesect U-Turns, opponent stays, Genesect user stays on the offensive unless they lack something else that matches well with the opponent (Genesect advantage)
And this is just presuming Genesect is in a situation to U-Turn and doesn't perhaps consider hard switching to, say, bluff a non-scarf set or bluff a choiced set and lure something in later. This is a simplification to some extent, but it still shows how Genesect's user is risking a lot less in a given match up with the threat of his coverage and ability to pivot as a consistently advantageous move.
4) XY Greninja still had hard stops and didn't necessarily have the power behind it to break a defensive backbone. You already mentioned earlier that Genesect has no hard counters, and I've affirmed it also lacks consistent answers. The thing that pushed ORAS Greninja to the breaking point was expansion to its coverage via Gunk Shot and to a lesser extent Low Kick. The point at which Greninja was banned it was in the position Genesect is in now: it had no consistent answers, only mons that could check some variants of it, but whereas Greninja was movepool adjustments, Genesect differs by entire sets. Greninja also lacks some of the tools that play into Genesect's proficiency, such as viable mixed offensive stats (Gunk Shot was only enough as a SE coverage on otherwise hard checks), which less consistent or not, are still backed by Download
+1 252 SpA Genesect Ice Beam vs. 0 HP / 0 SpD Arceus: 119-141 (31.2 - 37%) -- 78.5% chance to 3HKO
+1 0 Atk Genesect Iron Head vs. 0 HP / 0 Def Arceus: 129-153 (33.8 - 40.1%) -- guaranteed 3HKO
252 SpA Life Orb Protean Greninja Ice Beam vs. 0 HP / 0 SpD Arceus: 140-165 (36.7 - 43.3%) -- guaranteed 3HKO
Remember that if we consider Download and Protean give the same 50% power increase, Genesect isn't getting an item's power and still comes within a similar range on an invested stat. If the Genesect has a Download Boost on its STABs, the difference is even smaller without investment OR an item. This power only gets closed further if you allow Genesect to consider item options or the favorable-but-possible scenario of these factors lining up perfectly (ergo ATK Download on a Physically invested set like Shift Gear). This is all just comparing difference in power. Besides that, I'm not sure if I agree with the notion that Greninja has better coverage than Genesect. The former's viable options typically consisted of Water, Ice, Poison, Fighting, Dark, maybe Fire through HP as either primary or common secondary options, while Genesect brings Bug, Steel, Fire, Ice, Electric and off Water/HP Ground options. They each have a decent array of types to fire off, but Genesect's movepool is comparable if not much more powerful in terms of those options actual moves (Poison on Greninja only being through its lower invested ATK stat), and while I will have to properly confirm this, including Fire, Ice, and Electric alone in that coverage pool makes for phenomenal coverage within just two slots.
Genesect also puts the above behind U-Turn, pivoting being a role that a typical Greninja wasn't going to fill in lieu of AoA. This makes Genesect a hard to block core breaker offensively, and he also generates momentum even if faced with an answer, something the Genesect user will probably know before the opponent does and can disguise reasonably well since U-Turning isn't exactly a move most users have to be forced into.
5) It is true that U-Turn's benefits are not restricted to Genesect, but I also don't think it's hard to argue Genesect is the best user of the move in OU because of the sum of all factors on the table for it. Besides being a fairly decent user of the move in terms of Power + Speed, Genesect excels at forcing switches because of the threat presented by his sets and movepool, a quality that further bolsters U-Turn since it reduces the opponent's firing off moves at the incoming mon or wearing Genesect down on the exit (depending on the speeds). Genesect's ability to force switches also means he does not have to outright rely on U-Turn to keep Momentum on his side, rather it's among the options he can use to do so. He can use U-Turn as much as a proactive as a reactive move, whereas the common use, as you described in your point, is mostly reactive to get momentum back from a counter switching in. Genesect is just as free to U-Turn out of a weak match up as a strong match up, and for reasons such as the ability to bluff or simply the decent power behind its neutral STAB U-Turn, the choice's benefit isn't limited to the Momentum grab. And even if the above is something that can still be applied to any U-Turn user I'll ask again: does any other mon have nearly as many strong points going for it (set versatility, coverage options, overall/mixed power, strong defensive typing w/ acceptable bulk) at once as Genesect does?
As for the notion that Genesect is "uncompetitive", I have read this a few times in this thread and I cannot understand how in the world a word that has been rightfully applied to previously ban-worthy elements such as Swagger, Baton Pass chains, OHKO moves, Moody and etc. is now somehow applicable to Genesect. If anything, Genesect actually raises the level of skill inherent in a battle because contrary to many arguments that I read, there is in fact a difference between guessing or true unpredictability (or the dreaded "50/50s" term that I despise"), versus intelligent scouting, team preview assessment and risk analysis for your turns. Writing off the latter by simply saying "gee I have not one clue what my opponent could possibly be running and I have no way at all of figuring it out" is laziness -- you can argue reasonably that it might be difficult, but not that it is impossible. If you want to play this game on autopilot, there are plenty of teams that will allow you to do that and boy do we have a ladder just for you, but that is not the standard that we should strive for in terms of the most truly competitive areas of the community. Just because you think a scenario is a "50/50" does not mean that it is so; far too often I have either seen replays of a turn labeled as a coin-flip or have experienced them myself when, in actuality, whether we are talking about Genesect, Aegislash, Bisharp, Landorus-T vs Talon etc., there are plays that can be considered objectively "better" than others, where the reward outweighs the risk and you have some basis for your decision. So if you have a quarter nearby when you face Genesect and flipping it heads-or-tails is how you make decisions about how to deal with it, please do not vote. But if you do vote, and you do vote pro-ban, that's totally okay with me: just don't say that Genesect is "making the game uncompetitive" or "taking the battle out of my hands" because it makes you uncomfortable to play against something that can run multiple sets with set-dependent or team-based coverage.
Finally, let me bury the "checks and counters" argument in the grave where it rightfully belongs, for this suspect and future suspects. Yes, we are all astute enough to understand what it means to be a check vs a counter, how certain sets of certain pokemon are countered by certain sets of other pokemon. It is not a difficult concept to grasp. Consequently, I don't think any reasonable anti-ban poster here is trying to argue that Heatran counters LO HP Ground Genesect, or that Mantine checks Genesect variants running Thunderbolt. Obviously this is not the case, no one ever said it was. Rather, there are factors at play during an actual battle based on a variety of variables (your teammates, their teammates, what Genesect has done in prior turns, if it is shiny/not, what coverage is likely to exist based on their team preview, etc.), that can help you determine what play your opponent is likely to go for. Yes, for Genesect and for almost every single other OU viable pokemon, there are going to be turns between now and Gen 8 where you are out-predicted and out-played. Do not use this as an excuse to say that Genesect is unbeatable. If you think Ferrothorn can check Latios and you die to HP Fire, or Heatran is your check and you die to LO Earthquake, or Ttar is your switch and you're 2hko'd by Specs Surf then guess what -- you got out-predicted, or you didn't properly scout Latios' set, or you just got out-played and lost your check. I have yet to hear a solid argument as to why scenarios similar to this one are broken with Genesect, as if it is the only pokemon that can effectively use its passable bulk and wide move pool to lure its checks. Furthermore, you cannot have it both ways as a pro-ban poster and say "Genesect picks and chooses its checks" alongside "Genesect has the coverage to check whatever your team needs". In other words, if you're saying Genesect functions as this solo-agent that beats what it wants to alone, then that is going to result in it running optimal coverage to pull off its own sweep or break walls itself, whereas the latter is saying "my team needs Thunderbolt because I'm weak to bulky waters", and so you can expect Genesect to run that. This is just one way of understanding what coverage it is likely to have -- assessing what it is actually meant to do on your opponent's team. There is a reason why RP, Scarf, Band etc. run almost always the same coverage per set each time they are used -- they all perform a specific function and it is up to you to determine what that is, whether it is playing a supportive role or a more self-sufficient one. It doesn't guarantee you knowing anything's set but it goes a long way if your opponent is using a team that is at all rationally built.
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So as promised, while I am not only prepared to refute why Genesect is broken or ban-worthy, I will go a step further and argue that its presence is something that we may find beneficial in the long term development of SM OU. What Genesect does, as I stated in many past posts, is allow you to make your entire team of six pokemon more capable of supporting one-another in a way that any versatile pivot inevitably does. The difference between healthy role-compression into an offensive pivot, versus unhealthy centralization of a defensive one like Aegislash is that with something like Aegislash, you are relying on your typing, bulk, utility and/or recovery options to actually check a specific group of pokemon. This forces you to run either specific breakers or sub-optimal coverage to overcome this. With fast offensive pivots like Genesect, Greninja, Tornadus-T, you don't have the bulk or the capability to outlast individual pokemon but rather you check something offensively with your coverage and speed, forcing something out of play and gaining momentum. This isn't a phenomenon that I think is in any way broken or contrary to competitive play - I don't know why the only way we are allowed to check things is by sending in an appropriate wall every single time. If this is the only way you know how to play then play stall or fat balance teams, but also know that this shouldn't be the only acceptable way to play or win. If you want to talk about risk vs reward, that's fine, but if that's your best argument against keeping Genesect then you need to answer for the fact that in every single tier there are always at least a handful of S-rank offensive threats that are difficult to justify using. How much "risk" did you really take on using Clefable, or Latios, or Landorus-T on a team in ORAS? It was a very limited opportunity cost and that was about it. Having versatile offensive pivots helps a metagame avoid becoming too reliant on team match-up and bringing specific breakers to beat specific builds. Refuting this by saying "but we don't keep broken things to check other broken things" is somewhat of a red herring, because even if it were true that Genesect is very broken, it is performing a function that is very important for something else to fulfull in its absence. Eventually you get to a point where you have too many offensive threats to prepare for but none individually deserve to be banned, where is where I feel ORAS left off and as such it becomes a match-up dependent metagame revolving around the same stale pokemon checking the same stale pokemon. I'm really hoping this won't happen to Sun & Moon.
I see where you're coming from, and while I share the sentiment on the Broken definition in regards to Genesect, I disagree in some respects with the other arguments
Uncompetitive: Later in the post you mention Genesect's ability to check opponents in an offensive manner by threatening them out with coverage and speed. Genesect is not mindlessly down to "enter and click U-Turn", a point you mention and I agree with, rather he posses the coverage to viably threaten a large portion of the OU metagame as well as U-Turn. Being able to check a certain set of mons and U-Turn out of his own answers in turn is by no means specific to Genesect, but the magnitude of the pool Genesect can offensively check compared to how much he has to U-Turn against (as opposed to being able to choose U-Turn among other responses) is significantly larger than any other pivot OU has or has had. In my personal opinion, when a mon has as favorable a risk-reward ratio as Genesect does both in what he does individually and/or what he is able to provide for a team in a single slot, it enters into uncompetitive territory because reaping the needed rewards from building a team with and using Genesect does not take the same degree of skill at the top level that other mons did. In past gens, mons like Clefable and Latios certainly offered immense reward, but it took a significant degree of finely tuned teambuilding to cover their weaknesses and in-battle skill to properly outdo your opponent with them. An improperly played (relative to top ladder or tournament level skill) Clefable will not do its job right, but it's entirely possible for a sub optimally played Genesect to still swing a lot of momentum and offensive pressure in its user's favor. Genesect is a step above a jack-of-all trades, as the amount of utility and benefits it offers to the team before having to compromise any aspect of it is significantly greater than anything I think OU has right now.
Checks and Counters: The issue is not the idea that Genesect lacks checks altogether, but the issue becomes that Genesect is more than capable of using whatever it chooses in response to what would-be checks it is most likely to encounter at relatively minor-to-no cost to its overall performance. In your Latios example, Latios did indeed have options to deal with common checks, but it in turn had to give up something in order to do so: using a moveslot for any of those cost Latios either Roost or Defog, two moves that were definitely important factors in the roles it was viable for; HP Fire in Gen 6 required Latios to give up its Base 110 Speed tier, which was a cost in a gen where said tier was getting crowded with other viable Pokemon with the influx of Megas alone; Specs comes with its own general set of issues, as it locks Latios in as Choice items do and thus meant it had to be that much better at predicting when the target would come in, not to mention being harder to hide since typical Latios would carry a Life Orb, a much more easily identified item than something like bluffing Choice Scarf/Specs with an Expert Belt. Genesect doesn't run into an immense number of roadblocks in his own right by changing up his coverage moves, and they're not necessarily any easier to scout for outside of the more obviously announced Douse Drive, which only solves the issue of having scouted for it in battle and leaves the matter of having a check prepared for it in the first place. And the two supposedly conflicting points you mentioned ("Genesect picks and chooses its checks" alongside "Genesect has the coverage to check whatever your team needs") are not necessarily jobs that Genesect does at the same time on one team, but Genesect possess both of these qualities and thus is well suited to a team in almost any situation barring an entirely different playstyle like Stall. It is just as easy to build around a particular Genesect as it is to add Genesect into the team late in the building process to patch up a hole, and it might not even be a hole that specifically needs Genesect compared to a role that many mons can fill and Genesect happens to be the best pick for, such as an offensive pivot or just a general coverage based balance breaker. Genesect is a mon that often already goes onto a team for a general purpose like Pivoting, but even when observing the rest of the team it still can take scouting to figure out how he's going about that job, and the Genesect user by all means should be just as aware of the ability to read the team.
Say they're running Tapu Koko, a mon that's stopped hard by Alolawak, but their team also includes Gengar, a fast mon with a Super effective option who can deal well with Alolawak. Is Genesect another Alolawak checked mon that they feel safe using because they have Gengar (and possibly other answers), or is Genesect running HP Ground as another means to beat Alolawak and create a winning scenario for Tapu Koko? In situations like this, the Alolawak user is always the one taking risks because there's a plausible (rather than niche/lure) outcome to how they have to adapt to either possibility: If they play as if HP Ground, Alolawak can't check a very dangerous mon in Genesect and they have to be careful of the pressure on their other checks; if they assume no HP Ground, Genesect could very well take out their most reliable answer to another dangerous member of the team. Unless the Alolawak user makes very risky/unconventional moves (such as bringing in and immediately withdrawing Alolawak to try and bait HP Ground), the Genesect user probably won't reveal the information that should govern optimal play until they've gained such an advantage that it won't disadvantage them anymore, and this is assuming said risky play works and the Genesect user doesn't take the safer option of switching/U-turning to withhold that information regardless. This is one particular scenario, but many of the proposed Checks to Genesect's sets are fairly viable OU mons, so it's not unreasonable to think a team would have answers to them whether they inhibit a Genesect set they use or not. The knowledge of what Genesect set a player is running and how it governs their actions in a battle is valuable information, and a good Genesect user is aware of this and will make use of the opponent's need to know, whether it's through offensive pressure the opponent can't respond to without knowing, intentionally playing in such a manner as to keep them second guessing, or even altering their ideal manner of play to feed a false impression of what the information is. This is why the ability to tailor Genesect's checks to either the player's whim or the team's need is a valuable tool inherent to Genesect as a Pokemon and as a presence in the tier.
As for your closing argument, I fail to see how an offensive pivot inherently reduces team match up, as it simply means both sides are going to grapple for momentum with each other since both are equally capable of running said pivot. Team match up came down as much to lacking many options to break a defensive backbone as being weak to an opposing offensive core. Is the suggestion that trends and teams became very defensive to handle the large number of strong-but-not-bannable offensive threats? In that case those teams are not using Genesect and he's either too weak to help break them down or too strong for the defensive playstyle to check the offense he promotes without becoming broken itself. For offensive teams, Genesect himself is powerful and overall makes the playstyle stronger since he provides ever important momentum to a playstyle that already thrived without him there to offer it in such a degree. Barring that, I don't see why Genesect would promote anymore variety, as he inverts the problem in a sense to "I need to check Genesect's common sets and answer those common checks", which given the power behind Genesect's sets both individually and as a collective presence to prepare for, is a very limiting set of options on the first half and something to keep in mind for the second. I'm sure your idea makes more sense than I'm making of it, but as presented I'm do not see anything to make me agree with Genesect as a healthy presence.
As a minor closing point, I also think Aegislash is not a strong choice for describing defensive centralization alone: while his defensive presence was certainly a major (if not the primary) factor in how he centralized the game, the strong neutral coverage of his STAB, ability to break said STAB's common resistors, and high offensive stats due to Stance Change made his influence a combination of high offense and defense, even if it leaned (much) more heavily on the defense.