here's what happens...
person A updates to big sur; all their apps work (perhaps some need to be updated); the experience is a good one. so they post here "apple got this right, the move to big sur was painless. am glad i updated"
person B updates to big sur; 2 important apps, even updated, don't seem to work. the update was long, messy. they post: "apple really dropped the ball on this; the move to big sur was a nightmare. am sorry i updated".
and so on. there's just no one answer for everyone. the trick (i think) is to research your needed apps (check with developers, or ask other users on this forum), and to look into people on your exact mac who've updated.
then, you clone your current setup (ie with carbon copy cloner), and... go for it, preferably when you have a day or two to sort things out if need be.
but for most people, it's person A or B; diving in, and then, if there are problems, complaining endlessly on forums like this one. most people don't want to own their behaviors, they want the universe to 'magically' fix everything (& here, the universe could mean God, the gods, saint lovelace, or... apple.)
end rant 🤷♂️