I was under the impression that most windows games copy and anti cheat protection won't work in Linux. It often has a kernel mode driver to prevent you emulating things, using debuggers etc.
What changed? Do game manufacturers make special versions with toned down anti-cheat specifically to run on the steam box/Linux?
No, simply 95% of games don't have copy and anti cheat, and some anti cheats run ok on Linux
Nothing. Majority of those games do not work, but they are small percentage of all games on steam. Most is just small time developers trying to hit some big niche for big money, like Stardew Valley or Terraria or Meat Boy.