Fanfiction reviews are a different beast, but I do know where you're coming from. I swear, the dumbest thing I've ever read, anywhere, was a blog post from an author whose book got a bad review in Kirkus, where he said, "Those reviewers are just failed, embittered writers, and they couldn't have known what they were talking about anyway because they were reading from a galley, not a finished copy." So many things wrong with that statement it nearly made my head explode.

And not writing in a particular fandom doesn't mean you don't know the canon! I watched Crossing Jordan loyally from Episode 1 to the bitter end, but never wrote any fic. You bet I know that fandom, though. Sigh.