I also recently switched to Lichess after using Chess.com for years. What tipped it for me was that I switched to an iPhone, and for some reason the Chess.com app on the iPhone absolutely obliterated my battery. I'm not sure what the issue was and maybe it's been fixed, but for a while it was just eating up battery life while playing like nothing else.
The servers for Lichess I find a little less reliable, but it's mostly fine. I also like the free-ness and ad-free business model of Lichess. I ended up donating $10. Overall Lichess is a better experience. Chess.com is perfectly usable without paying, but the constant nagging to sign up for a subscription is annoying.
It doesn't crash; it's sluggish. It's hard to quantify but it's like there is a quasi animation effect that you can't turn off. In something like 3|2 it's not terrible but in 1 minute games its a real issue.
I thought for a while that maybe I was just used to the lichess interface but I don't have the same sluggish feel when playing on my phone on the website vs the app.
The servers for Lichess I find a little less reliable, but it's mostly fine. I also like the free-ness and ad-free business model of Lichess. I ended up donating $10. Overall Lichess is a better experience. Chess.com is perfectly usable without paying, but the constant nagging to sign up for a subscription is annoying.