It is certainly an acceptable topic for this forum.
I chat about such things here, or in person. I'm not a big user of social media for discussion, because I think modern social media is actually pretty bad at supporting discussion.
Sword and Laser is a regular podcast covering written SF/Fantasy, and their Goodreads group is where listeners discuss the podcast, current books, and SF / fantasy novels in general. They do also have an area for discussion of other media including film and television.