New IMDb-like site with discussion boards for every movie/series/actor
It's called The Movie Db. They recently added discussion boards to all of the individual title/series/actor pages like IMDb has.
https://www.themoviedb.org/tv/66292-big-little-lies
The discussion board link is in the top left corner and looks like a chat bubble. No posts yet but that's because it's still brand new. Spread the word.