Or have I just not run into it yet?
It’s the ending
and the time period.
I said inspired, it doesn’t have to follow it completely, I’d rather fics based on movies not just be a regurgitation of the movie with Sam and Mercedes in it.
Even loosely inspired, the ending is still tricky sort of. I doubt anyone would just regurgitate it, but those reasons may factor into why someone hasn’t done it yet. I didn’t say it was a bad idea.