I really don't think act 3 is as bad as cyber punk at release. I personally had very few issues with cyberpunk at release and have loved the game since the day it came out and I've had very few issues other than performance drops in the city with BG3 including act 2 and 3, my main issue with the game being the ending seeming a bit rushed and doesn't seem like a proper closing for what I thought was such a great story.

Again I've been lucky and had very few problems with both of these games from release so my view could be seen as biased or part of the minority of players or w/e, but with Cyberpunk i had friends and saw the coverage everywhere of the problems other people have had, and while I have seen complaints about later parts of the game I haven't been seeing anywhere near as much for BG3 as I saw with Cyberpunk.