The main thing I’ve been seeing is that since it just picks up every airing series, it can create spam of the same series which is releasing multiple episodes at once. As well as posting discussion threads which routinely get 0 votes and 0 comments on them even after days from being posted due to being an extremely niche show.
The main issue I was seeing on Lemmy with Shinobu is due to the low popularity shows. We already have a much lower active user count than Reddit does, so a lot of automated discussion threads here get completely ignored. So this just creates a lot of clutter in the feed with posts on 0 votes and 0 comments.