I'd imagine everyone else has an agenda, a schedule and ordinary life which is pre-written, so the game actually wants to tell an interesting story, but as a player, you can choose to listen or just do all shenanigans in the context of the game you can come up with. If you want to be a farmer instead of defeating the dark overlord, so be it -- until the world ends because the overload has achieved his goals with no resistance, or maybe someone else becomes a hero instead.
...Gosh, the more I think about it the more awesome it gets.
Edit: just one more! Imagine actually having to complete quests in a given amount of time, because the rest of the world continues to revolve. People being mad at you because you left their children to die in the dungeon after arriving a day too late, because you were busy running an errand for someone else.
What I have been thinking would be really cool and fun to try would be to remake zork with llms, speech to text and text to speech.
I think you might be able to do it with a lot of prompting, and having a database that functions like a wiki for the current and past states of the game world.
If you got really fancy, you could also make it a pseudo MMO where the content of the story you create with a character could be used as the basis for a NPC plotline in other people's worlds, possibly reducing the amount of content needed to be written.
If it got popular you could also use it as a research tool, where you could force some subset of the player population have some interaction, and be able to test and get a dataset for counterfactual reasoning.
Edit: just one more! Imagine actually having to complete quests in a given amount of time, because the rest of the world continues to revolve. People being mad at you because you left their children to die in the dungeon after arriving a day too late, because you were busy running an errand for someone else.