Anyone sat through them all yet?
Pray, do explain the distinction for us rubes. It has been adapted by avowed fans of the books, who are also beholden to a popular audience and a mega-corporation studio with certain requirements, but the fondness for the source material is evident to anyone who studies it closely.
If you’re simply using fanfiction as a thoughtless perjorative, then carry on, but perhaps I misunderstand your meaning.
You seemed to already grasp what they mean when you said in a different comment that you already have the books to reread, and that this is a different thing. The closest thing to which it could be an adaptation of is the last 50ish pages of the silmarillion? It had some pretty big structural changes to that in season 1 already, so I don’t think fan fiction is an overly harsh description.
Besides while it is often maligned, fan fiction is fine. It is okay to like fan fiction.