Baldurs Gate was originally made with the idea of translating a D&D to video games, so it's kind of crazy to abandon the system like that. And you basically just described an arpg
Sure, one cannot completely change nature of D&D when making game based on D&D structure. I was talking on RPGs systems as a whole.
I call bullshit on claim that one can analyse battle situation of 10+ characters all making attacks, activating abilities and casting spells at least once every 6 seconds. Hell, in modern titles (Kingmaker) preventing units from activating bunch of opportunity attacks and killing themselves is a nightmare alone, not to mention doing anything coherent, unless dice is already in your favour (and therefore it doesn't really matter what you do).
It's rather hard to keep track of all the things going an at once for sure, and that's not merely the to-hit-rolls, but also concentration checks, checks on concealment, etc. etc. Owlcat's next game is going to be turn-based Sci/Fi, btw. Probably based on Starfinder, which equally is based on Pathfinder/D20, but they've yet to announce it.
I found the combat mostly more fun in Deadfire -- even something as adding the simple combat speed slider did so much to the experience.