It's about more than just posting, you log movies/tv/other kinds on-chain, so you can always have a copy of what you've consumed. Then you can do more with that by comparing to other users to check what they've consumed, what you may have missed, what they like, comments/reviews they've left on them, etc. The scrobbling extension also allows for automatic logging of music and certain streaming platforms that work on the browser. Worth taking a deep look at all the functions. Idea is that it's not just another posting front-end but offers more.