Several games with anticheat work. But it's up to the developers whether they check the box that allows it to work, which is why even though both Apex Legends and Squad use Easy Anticheat, Squad works and Apex does not.
Of course some anticheats aren't supported at all, like EA Javelin.
Apex Legends is an interesting case because EA/Respawn initially shipped with first-class support for the Steam Deck (going as far as to make changes to the game client so it would get a "Verified" badge from Valve) -- including "check[ing] the box that allows it to work". However, the observation was that the anti-cheat code on Linux wasn't as effective, so they eventually dropped support for it.
Of course some anticheats aren't supported at all, like EA Javelin.