Very subjective opinion about the UX.

I much prefer chess.com's UX. They allow multiple pre-moves vs. lichess that only allows 1 premove, has much better cheat detection and overall much better handling of players who engage in bad behavior (abandoning lost games) by segregating repeat offenders into a pool of their own so they don't affect well behaved players, and lichess has a very quirky and unnecessary 300 move limit, which one can argue is more than enough for regular chess, but for speed chess is just a nuisance.

I've played speed chess for years, and I have never hit 300 moves in a game. The only way this will ever happen is if both sides are intentionally trying to avoid 3 move repetition.

And in terms of premoving, chess.com spends 0.1 seconds per premove whereas on lichess it's instantaneous, so I've found games tend to last longer on lichess move wise.

Sounds like valid reasons. I think we have different preferences - I like the lichess aesthetic, unlimited free puzzles, engine evaluations and opening explorer and lack of freemium popups.

Hope you enjoy your games, and your preferences seem reasonable too!

Also lichess has good number of variants, for example its very easy to get a game of CrazyHouse in lichess, whereas can you play CrazyHouse in Chess.com.

How does lichess handle abandoned games? About half the time I don’t even get to claim the early win and i can see the other player is already playing another game

If a player leaves your game, lichess gives like a 20 second timer and then lets you claim victory. I believe there are also "offer draw" options, but I'm not sure.

Oh is it not a thing on chess.com? Ime lichess abandoned game detector is not super reliable but i guess better than nothing

Chess.com has 60 seconds countdown after leaving a match (at least in 10 min mode, haven't played others that much). Also, in daily chess there is a time limit for every move. Failing to move on time results in automatic resignation

You can claim victory or a draw in that situation.