And if a cheater makes it non obvious by being a bit worse sometimes, and has become indistinguishable from a regular or just really good player, then... Mission Accomplished? At that point, it's no worse for the other players than playing with someone who is organically good, unless the sanctity of some matchmaking algorithm is more important to them than the gameplay.

Which is fine too, but the solutions for that problem may ultimately need to extend our be situated beyond the game software itself.