I think lichess has pretty sophisticated techniques to detect cheating. They take it pretty seriously. I’ve played thousands of (non anonymous) games on lichess

I think lichess has pretty sophisticated techniques to detect cheating. They take it pretty seriously. I’ve played thousands of (non anonymous) games on lichess and I might have played against someone who was cheating once. If you play without logging in, you’ll probably find more cheaters but it’s rare even then.