The problem with the the party banter is that it's all predictable and shallow. They party don't say anything that suggests more depth than you see on the surface. We don't see further insights into them as characters nor do we see any interesting dynamics develop. To use Dragon Age as an example since I don't know BG1/2, the friendship between Isabella and Merril is unexpected and enhances both their characters. Similarly, seeing the contentious relationship between Merril and Anders and the push and pull between them lets us see different aspects of their characters come to light. We don't learn anything new seeing the banter in BG3. There's no sense of growing camaraderie but at the same time there's no tension or clashing beyond Lae'zel and Shadowheart. It's all shallow interaction with no deeper insights. We don't see unexpected friendships or clashes or anything like that.
I wonder if part of the problem isn't that every character besides Lae'zel starts off with some kind of secret so until those come out into the open, however long that takes, they CAN'T have interesting interactions because they can't discuss the major aspects of their characters and the things that follow on from that. Also, does the rest of the party even know Wyll is a warlock? It doesn't make sense that they would since he only talks to Tav about it. Same goes with Gale. Which means that those are two characters who logically cannot have their major character things talked about by thew party at large. Frankly it's weird that the rest of the party knows Astarion is a vampire. Based on how the scene plays out, they should be none the wiser.
