Yeah, I’ve decided to define this genre as 1. By a single author, and 2. In the form of either a review of, or a personal reminiscence or non-fiction article about, a movie that doesn’t exist in our reality (otherwise I’d have included Camelot Studios Presents https://archiveofourown.org/works/17682371/chapters/41707190, an Arthurian AU in which the characters are making a movie.