It’s not 100% clear why Larian didn’t include these features in the toolkit to begin with, but it may be a case of protecting certain copyrighted assets being scraped easily from the game, or from being altered in a way that is unpleasing to DnD’s intellectual property overlords.
Super duper cool that this was done, I just worry that WoTC/Hasbro will mandate this sort of thing needs to be squashed. The new DND system is focusing heavily on a virtual tabletop system under a subscription plan. While standalone BG3 isn’t a threat, a modded full custom campaign could be seen as one. I wouldn’t even bring this up buuuuut between sending Pinkertons to collect MTG cards and the OGL crackdown, seems like any scummy move could be possible.