If you allow everyone who cheats to play, even if they're only playing at the peak, it will break the balance of everything. The top tier games will suck because half the players are cheaters, and the lower tier games will be filled with aimbot smurfs on their way up.

Unfortunately pretty soon we are going to enter a world where the cheats can be deep learning based and entirely external to the game itself (only using video as input, transmitting raw mouse input, etc). It will be fundamentally impossible to tell the difference from human players. This will be a weird time for competitive games when it happens.