I myself do not know the actual post which are specific to pob community unlike CTP, Stem, weed, natural medicine and sports ltalk etc that have barriers to know you can post or tag to post in there community.
Exactly-- The communities and/or tribes you noted have a specific focus. Proof of Brain is open to all topics.
At any given moment some topic or other is the topic, and that's what I'm trying to determine before I post. If my post is on a topic no one cares about, then no one will read it. No one wants to see 0 upvotes with 0 comments.