No, to get it out of the way, I didn't. I started DA, didn't like it much and discarded it pretty soon - which was not solely due to the game but also due outside circumstances. But I don't need to, in order to know that I don't like being stuck in a menu for dialogue for dialogue's sake. I like an experience that is balanced between gameplay and story - which BG3 does.
And I think there's our point of disagreement. I also think that efficiency is key, but for me efficiency means deploying your resources in a manner to best realise your goal. (Not to make the most people happy.) For example, I got the feeling that all the (Wizard) dialogue was written with Gale in mind, which is great if you play Avatar-Gale, and is fine if you play a custom Tav because the wizard dialogue usually circles around the universal flaws of the class. Feeds two birds with one cookie, wonderfully efficient.
But I also think that dialogue should be efficient. "A good screenplay is an efficient screenplay." is something I once heard and that I agree with. Dialogue should have a purpose and ideally achieve several things at once. Take the banter between Shadowheart and Lae'zel about burying the hatchet, it's a fun dialogue on surface level, but it also tells you a ton about Lae'zel and a bit about Shadowheart on a deeper one. It also progresses the story by resolving their confrontation. The clip you linked does none of that, its only purpose is for the player to feel more important because they can make a selection - what I flippantly called a desire for the companions to fawn over your PC. It's not something I consider very valuable because to me it's basically bloat, that I am stuck in menu for. I hope this explains why I do not generally agree with you about more content.
So when I think about reactivity, I'd think about what would need to be explored further or add value if it was - asking the Gondians about Karlach's heart comes to mind. (A specific example instead of a general ask for more.) And it's apparently something they really didn't want to change. I can't tell you if it's because they were happy with it or what not, the much requested hug for Shadowheart during her Selunite graveyard scene was added later on, so someone appears to have liked that idea.
