What makes Ice so powerful in the current metagame is all the unique attributes it has as an offensive type despite being a terrible defensive one. Snow giving x1.5 Defense is a huge change this generation which makes setup even more deadly behind the already automatic Aurora Veil, with Baxcalibur being the prime example. Alongside being able to set screens and largely beneficial weather, it has a good hold on keeping that support system up with Alolan Ninetales being able to beat a primary weather setter in Pelipper and Ice as a whole is good against Defog users with the majority of them being taken advantage of by Baxcalibur. Brick Break and Psychic Fangs users are honestly not that common in the current metagame, with many of them being beaten by Alolan Ninetales or Chien-pao; if you really want you can run Froslass for the immunity. Personally, from Ice's impact I can't really say I see Baxcalibur staying in the tier as time goes on; I feel like it scuffs teambuilding and playing immensely and far from the point of where it would be considered healthy. Its combination of power, coverage, bulk, and ability makes it super hard to deal with defensively even without all the additional support Ice provides.
From a building sense, Baxcalibur does have common "answers" that can beat it 1v1, but they're for the most part not sufficient long term. It can be argued that Pokemon like Sableye, Quagsire, Kingambit, and Galarian Weezing all answer it in some way, but they're all mainly situational. Sableye can only beat it if you switch it in on a setup turn, which isn't reliable considering with Scale Shot Baxcalibur does not need to click Swords Dance to win. Quagsire 1v1s it with Toxic but is held back by 8 PP Recover alongside the fact that Ice teams carry Spikes a lot, not to mention that Substitute Baxcalibur can take advantage of it as Earthquake does not break Substitute under snow. Kingambit and Galarian Weezing only beats it if it's unboosted and not under Aurora Veil or snow (in the case of Kingambit), which is unrealistic. For the most part, players are going to be relying on a combination of factors to beat Baxcalibur consistently with the support at its arsenal.
I feel like a lot of other teammates that Baxcalibur has is overlooked apart from Alolan Ninetales. Alolan Sandslash is an incredible remover and ensures that hazards are not on the field with Knock Off to threaten spinblockers unless you're going against a Ghost team, which means you can pretty much count on Baxcalibur not taking hazards damage when it comes in. If Baxcalibur's taking hazards damage, then you're probably against Ghost and Chien-pao eats that anyways. Froslass's Spikes are super annoying to any team not named Flying, and if you're Flying, well, Baxcalibur owns you regardless. Personally I would love to see Ice in a practical setting being used in tournament play and gauge Baxcalibur's impact from that, but I don't feel like any metagame development that happens around Ice being powerful would be healthy in a major team tournament such as MWP. You would almost never be using something like Dondozo, Iron Defense Corviknight, Tyranitar on Dark, Brick Break Scizor, or defensive Gyarados in this stage of SV Monotype if not for Baxcalibur, which shows how metagame warping it can be. The fact that someone can load up Ice and automatically have a really good chance of winning like 14/18 matchups (sucks against Bug, Fire, Fairy, and Steel) shows how powerful the support is. It's incredibly hard to account for in the builder for a majority of types, and a big indicator of this is that it definitely seems like the metagame has been divided into two categories since DLC 1 dropped: teams that can handle Baxcalibur Ice and teams that can't.
In my opinion, the best way to handle Baxcalibur would be through a community suspect test as soon as possible so that it doesn't interfere with MWP in the winter. Banning Light Clay or Icy Rock doesn't make sense as removing the former restricts healthy archetypes like screens Fairy and Dark while the latter can easily be replaced by the former (and is probably the inferior item regardless). Neither of them are actually the problem; in reality Baxcalibur is.
For the rest of the metagame, nothing really stands out to me as broken right now; the closest thing would be Urshifu-S but the metagame being this offensive hurts it somewhat. Chien-pao and Kingambit both seem pretty tame; Chien-pao would be a lot more broken but then GameFreak decided to give every other Pokemon and its mom Vaccum Wave which has owned its viability somewhat. I still feel like losing to Kingambit is more or less bad building or playing in this metagame, Pokemon like Gliscor and Mandibuzz coming back really hurts it coupled to it not being too threatening pre-DLC. For now, it's just a really good Pokemon that pulls off a sweep with smart play.