I think @Tuco and @Ranxerox nailed it.
The Larian CEO has never liked DnD and always wanted to make DoS3. At first they tried to make BG3 as DoS-like as possible and got frustrated when DnD fans pushed back.
As far as staff being elated it seems cleathat the CEO tends to confuse his staff's reactions with his own. I've worked for bosses like and it was a pretty awful experience. After a while you start to lose your sense of self because you spend all of your time sharing your boss' fears, anxieties and moments of elation.
As the CEO said:
"There are a lot of constraints on making D&D, and 5th Edition is not an easy system to put into a video game. We had all these ideas of new combat we wanted to try out and they were not compatible."
Act 3 is a mess and it's the most Larian of the chapters. Explosions, barrels, everyone-hates-the-gods, undead as comic relief. It's the chapter that wanted to be Larian game but was forced to be DnD game.
So, sure, I will probably buy DoS3 once it has definitive edition and is on sale.
This is yet another signal that the end game will not be improved and that's a disappointment but, on balance, this is good news.
Hopefully BG4 will be made by a company that likes DnD.
