This is partly because chess.com's game report "accuracy" Computer Aggregated Percentage Score (CAPS) is misinterpreted by many. It is more of a "report card" on how well you preformed in your game than it is some exact science. Plus, you can get a different "accuracy" for the SAME chess game if you run the analysis at a deeper depth.
The other reason why is because the rating estimates also use the player's rating as a baseline for their estimation. chess.com has mentioned how they plan to replace this "rating estimate" feature with something more reliable in the future.
In the meantime, here is an old clip regarding "Accuracy."
Hello Chess.com community I hope you are doing well. I recently played a blitz game where me and my opponent both had the same accuracy (80.7) but had a completely different rating estimate
mines was 1700 while my opponents was 1450. Why is this?
Heres the game for anyone who wants to see it
https://www.chess.com/game/live/82780886619