The site has performed more or less the same after the staff cuts as it did before. I say this as somebody who has used it nearly daily for ten-ish years now. Most users I know have the same experience. Maybe you noticed something if you're parked on Twitter for hours at a time, but I try to limit my exposure to people that do that.
I get that Musk is a dipshit and that there are other problems with the site since the change of ownership, but the griping about stability seems to come from people that don't actually use it.