It's annoying to play against cheaters and/or sandbaggers, that's for sure. But it's also very hard to combat against.
Mostly, all you can do is report the opponents who you strongly believe are cheating, and let Chess.com take care of the rest.
But yes, I share your frustration ...
https://support.chess.com/article/648-what-do-i-need-to-know-about-fair-play-on-chess-com
https://www.chess.com/article/view/online-chess-cheating
https://www.chess.com/article/view/chesscom-update-july-2024#FairPlay
The site closed almost 60,000 accounts in June for fair play violations and has a full team of staff working on reports along with some automated systems for detection.
https://www.chess.com/article/view/fair-play
That said, discussions of cheating, potential cheating, or cheat detection are not allowed in the general forums. If you would like to discuss join the following club once you've been a member for at least a month. https://www.chess.com/club/cheating-forum
I’m a completely amateur player and play a lot online, but it’s unpleasant and discouraging when you see that a player doesn’t take time to think and attacks so quickly that it would visibly take some time to calculate if the move makes sense. Or you see completely different games with no definite openings, just moving pieces haphazardly, and then suddenly they become a genius. It’s either they are cheating or they are very good players far above the level they are playing at, between 500-700, which doesn’t make sense as they are not learning anything. So it’s easier to believe they are just cheating.
This is just a rant because if I wanted to play against a robot, I wouldn’t need to play online; I’d just play against chess.com’s algorithms directly. Please create something verifiable, or the quality of the site will just depreciate more and more because it’s very easy to make fake profiles and use algorithms to cheat.