>>51321855They have a bias toward tourneyfags. In a tournament, one loss can mean the end. So they try to reduce risk as much as possible. Every Smogon ban stems from this.
Stall is generally a very low-risk playstyle. With so many turns, any individual turn becomes less impactful. So Smogon favors it a lot.
Evasion, despite objectively being a stally playstyle centered around prolonging the battle, is banned because it's also RNG-centric. Same goes for sleep.
Highly offensive and volatile mons are good, but not as consistently good. When using something like Garmanitan or Dracovish, you're often just hoping your opponent guesses wrong, and you insta-win if they do.
Rather than thinking of Smogon as banning things because they hurt stall, think of it as them banning things that would really piss you off if you lost to them.