I think most games, especially role-playing games, fall short in the final act. Despite that BG3 is still well worth the price of admission, though I'll think twice before joining another early access.
I hope Larian consider keeping up with the game now that it's launched, but I've gotten the impression from interviews with Swen that he's a bit 'over' it. The amount of work it would take to rejigger the main plot in BG, might just not be worth it for the number of people who think the problems with the narrative are serious enough to even warrant it.
Well, who knows how much work that would take? This entire game is 6 years in the making. Taking into account that there are already plenty of datamined content/ideas to be re-purposed, you could definetly fix this game in one and a half year, and resell it as a definitive edition imo. People like me would buy it. Ofc they can just not do it, and people like me will never come back. Their choice.
There is also plenty of really good ideas on this forum that they can implement.