I think I've played on about every chess site there's been. The worst type of cheater, on the sites with no moderation (unlike chess.com) will play about half their games on their own, and the other half with an engine (to keep the ratings low). The people who used an engine every time are easy to avoid with high ratings and near perfect records.
And of course it was easy to tell. They would play like a near beginner one game, then 15 book moves the next.
Chess.com is one of the best places to play. They actively seek and ban cheaters.
One thing to know in turn based chess is it's legal (and to some extent even expected) to use a database or book for the opening phase. Not an engine which finds moves for the player, but reference material.
Some people let the fear of cheating turn them off to live chess completely. I think that's a shame. There are plenty of honest players out there.
You might call me cynical, or just devoid of trust for online chess anymore. I have seen the internet develop (and deteriorate) since the early 90's. So you are right, if you assume that I'm a middleaged man with life experience.
But I have reached a point where I just want to learn human chess as good as possible. Since I didn't take any interest beyond piece movement in my earlier years, I have to recuperate the chess understanding from scratch.
I do of course have a decent IQ with some skills in mathematics and logical thinking, but that won't suffice in an empirical sport like chess.
I will stay in this chess mentor as much as possible, and occasionally try out my knowledge against turn based players (whether they are humans or not). I will stay human.
Any other likeminded skeptics of today's online chess out there ?