Here we go again. One game I was excited about was the upcoming Mecha BREAK, which currently has a playtest demo on Steam but they've added in anti-cheat.
It drops the graphics to their recommended settings, but you're free to crank them back up to anything you want. No, it doesn't check in any way. I have no idea why you would do this, it basically only means anyone who doesn't check Proton DB for config advice will think the game is half broken.
Eh? I don't understand. Either it works on Linux, or it doesn't. Seems like the author just doesn't know how to troubleshoot some compatibility issue on whatever desktop Linux distro they're using.
ACE (Anti-Cheat Expert) seems to work only on the Steam Deck, but doesn't let you play on any other hardware running Linux. Delta Force has the same issue