This would be a bit disappointing to me. They spent a lot of time authoring interesting and crazy utterances that were often absurd and funny in their previous games.
(Don't think LLM charaxters are ready for realtime use on that kind of game soon enough for the game being discussed, but I don't think it would have to compete with creative character line writing as much as being a force multiplier for it when it is ready.)
Putting it in the critical path will take a lot of development/testing.