Generative “AI” is not “AI”, it’s a overlarge statistical model of written language. It cannot make NPC dialogue more lively because it has no concept of “liveliness” or “boredom”. A 10-minute conversation is impossible, anything more than a few words and the models very rapidly lose consistency. You can see this for yourself by playing one of the many “AI Dungeon” attempts at using large language models to run a text adventure.