There's definitely a great documentary to be made about this subject but by ANYONE other than this director who seems content to just string together trailers (with no captions to tell you what the movie was) and interview subjects telling amusing anecdotes from shooting these crappy movies.
This needed a framing narrative explaining the whats and whys of the genre, some look at the major players, tropes, etc. Instead, we get nothing but interviews (shot with a terrible side angle used for who knows what reason) and clips from (mostly Full Moon movies).
Like literally ANYONE could have done this better...