Earlier quoted context omitted.
What would be the point of a competitive game if you could just cheat? Racing games like Trackmania live off verifying people don't cheat because it's a game where people compete for leaderboards. Should they not be allowed to prevent you from cheating yourself to the top of the leaderboard.
Games like Trackmania should have SERVER SIDE data input validation instead of pushing rootkits.
CS:GO faces the same issue where inputs by high level players are indistinguishable from cheating.
Speedrunning tends to have similar issues, where people perform tricks that are so close to TAS inputs that it can take years to spot an issue. Or in case of Dream, it takes an entire statistics paper to explain why they cheated. In those cases it's even worse because you cannot do server side validation on video data.
Being against anti-cheat is effectively being against competitive gaming or speedrunning.