The latest Proton experimental version really improved over this(talking about battleye anticheat). However the game vendor still has to make a minor change in

The latest Proton experimental version really improved over this(talking about battleye anticheat). However the game vendor still has to make a minor change in most cases.Usually nothing starts if the anticheat doesn't approve it, so in most cases right now games that use anti-cheat on steam don't work because of "normal reasons"(i.e not using some special graphics flags, use vulkan/etc) not because the anticheat itself.