And that's all I am saying, and it is not a concept I want to be objective due to magic in video games.
Well, as much as I agree with you, BG3 is set in the D&D multiverse and good/evil & law/chaos IS an objective concept here - I don't exactly like that part, but it is what it is. So certainly the arguments for alignment are stronger here than in most other uni/multiverses. For instance, Raphael - a devil - is an essence of lawful evil, and actually must obey a very specific "truly lawful evil" morality - lawful evil mortals would generally have a much broader set of worldviews, behaviors and moralities than the devils and beings inherently connected to Baator.
So there are really no strict rules applying to mortals with free will, certainly not those races created by non-evil gods. And generally, in 5e, it is really not used much in mechanics, spells etc. Honestly, PC's alignment in 5e is a weird thing, e.g. read this rant if you have the time
. The way alignment is handled in 5e makes me say: Screw alignment for all non-celestial/fiend characters, avoid if at all possible - but the objective nature of good, evil, law & chaos in the multiverse will manifest itself sometimes.