I'm still afraid to run Catalina. I have to use it on one laptop (me hardware) an it is slow and problematic. I've had actual system crashes. I can't remember the last time that happened pre Catalina
A few years ago I remember reading an article where Apple looked at crash metrics and worked very hard to address those. The criticism at the time was that this wouldn't catch slowdowns, hangs, or issues like "why aren't my Messages showing up?" which has been issues more recently.