I play correspondence since many years ago. I have been playing in lichess for years having a rating ~1900-2000. I recently open a premium account in chess.com and I started to play 50 simultaneous games. I couldn't pass throw 1500 rating while my tactics trainer rating is 2600 and I returned to play in lichess.
I know there are some reasons why chess.com has stronger players with the same rating than lichess ones, but analyzing the games I faced players that do have plus than 95 of accurancy in complicated games, so I think the reason may be those player use engines at least when the move is complicated, as they are rated 1500 and not making blunders. This is not what I found in lichess where profiting of blunders allow me to beat easily 1500 or even 1700 players.
I read a post of Erick, the owner of chess.com saying cheating happens at a +2300 level. But my concern is, at a lower level and in correspondence, I miss blunders in chess.com. In lichess I have not troubles to reach 1900-2000 rating beating easily the 1500 players. I think those users are using engines when the position is complicated but playing a fair game the rest of the game. That might evitate them to be catched and allow them to play at a 1500 level while they are poor players that should have a rating <1500. I have seen other users that have a curve of rating that grows and decreases. I think when they loose rating they start to use the engine so they can mantain a rating and play the games they want to play with overrated players than them.
chess.com is a big entreprise, they should have programmers versed in machine learning techniques to detect cheaters. Are lichess programmers better than chess.com and succeded to send cheaters away from his correspondence rooms even at low rating levels while chess.com programmers not? Do they use similar technics or lichess ones are more sofisticated?
Or it is just a matter about rating strenghts and I am being paranoic? It might be just 1500 rated players make blunders in lichess while chess.com 1500 rated players not?