I'll be like those Southerners that still hang Confederate flags even after the Union won and refuse to put more than one Pokemon to sleep at a time in my battles.
to give this post a little more content, I think that Substitute users will be a cool way to prey on Sleep users who will inevitably see a rise in usage, at least in the short term. Outside of the benefits they already possessed, like dodging Intimidate and burns, being able to essentially make the Sleep user waste their turn while having a Pokemon behind a Sub is a great position to be in, so I think that Substitute users will be that much more potent post-Sleep clause