There will never be a forum comparable to IMDb. It was a vast site, and completely unmoderated. I couldn't believe the stuff that people got away with saying. Sometimes stuff got flagged, and then the post or thread might get deleted. But aside from that, anybody could just post anything. Oddly, curse words weren't allowed, which was a joke on that site, since they would probably only have improved the quality of the conversations.
If the boards for the movies and TV shows weren't bad enough, the general boards were even worse. They had boards for miscellaneous stuff like pets, fashion, automotive, music, etc. From what I can tell, the busiest of all was the Politics board. It was also the most disgusting, trollish, bigoted, and opinionated.
Shortly before the forums were shut down I saw a thread that said, "I went to Macy's and took a poop in one of Ivanka Trump's shoes." That was the actual name of the thread. And what's more, it was one of the more high-brow threads there. And it got several replies. So the person started another thread, this time about wiping his hindquarters on one of Ivanka Trump's dresses. And this was on the board for Politics.
I wonder where some of these people will end up, now that their old stomping grounds have been shut down. Other forums expect people to have conversations that are actually coherent, and relatively polite. The IMDb trolls and wise guys might have to change their style.