I am going to oppose the general view. I think the generic non-specific dialogue is a reasonable idea. There are 4 origins, each of which should have a different personality and history which colors what they say.
Would a specific line really fit all 4 origins (never mind the additional origins still to come) and the generic dialogue?
There are hundreds of these generic dialogue choices in just the first act. It's not feasible to rewrite each of them in 9 different ways, so that leaves only the option to have one generic line lacking any personality or context. That's not going to be any better than the generic lines which encourage you to use your imagination to decide what specifically was said.
Larian has had good dialogue for the player characters, but that was absent from D:OS 1. Origionally it was planned that dialogue with NPC's was just going to be keyword based. No one liked that idea - and there was indeed a good argument against it, as one single word didn't provide enough context for what the reaction would be.
The transition back to full written lines had as its main casualty Larian's trademark wit. (Well possibly the EE brought it back, I'm not sure). The Vanilla version of D:OS 1 the protagonist dialogue for conversations with NPC's was pretty generic. I'm not sure that trying to go to specific lines will work any better.
