Unpopular opinion, but we would be better off with a single open trusted implementation of anti cheat (aka drm) which can attest whatever requirements are desired by the game is met. The only real problem is that it would likely be limited to approved kernel images and someone would need to own that validation and signing infrastructure, but you could imagine having multiple trusted entities have this role.
Imagine wanting tivoization. Horrifying.
Kernel anticheat is not really effective because it can be circumvented on the hardware level, for example using direct memory access with a second computer and screen to show the hidden game state.
Cheating is a meat space problem and there is no technical solution to it. Thats why in tournaments there are referees standing behind the players. Ultimately it comes down to checking if metrics like reaction speed are humanly possible, but a rootkit is not really needed for that.