Although this is true for most games it is worth noting that it isn't universally true. Usermode anti-cheat does sometimes work verbatim in Wine, and some anti-cheat software has Proton support, though not all developers elect to enable it.
Looking at you Rust.
Edit:
And the rest of you. If even Microsoft's Masterchief Collection supports it, I Don't understand why everyone else does not.
It's because the Linux versions of those anti-cheats are significantly weaker than their Windows counterparts.
Anti cheats are as much a marketing ploy as they're actual anti cheats. People believe everyone is cheating so it must be true. People believe nobody bypasses the FACEIT anti cheat so it must be true. Neither of those are correct.
Riot revels in this by marketing their anti cheat, but there are always going to be cheaters. And sooner or later we will have vulnerabilities in their kernel spyware. I much rather face a few cheaters here and there (which is not as common as people make it to be on high trust factor).
You think tournament organizers or pro players know the first thing about anti cheats? They buy the marketing just like everybody else.
I’ve seen so many players saying “look you can own my entire pc just please eliminate the cheating.”
It would be great to see more of a web of trust thing instead of invasive anti cheat. That would make it harder for people to get into the games in the first place though so I don’t know if developers would really want to go that way.