too many cheaters


The perception of cheating levels is orders of magnitude more than the actual amount. The vast majority of games and players are clean.
Regarding brilliant moves, lower rated players sac material all the time. Most of the time it's not going to be good but they'll still get brilliants in games. That said, if you suspect someone, you should report them.
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-march-2025#FairPlay
The site closed more than 100,000 accounts in February 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 want to discuss join the following club, once you have been a member for at least 30 days
https://www.chess.com/club/cheating-forum