I am led to believe this is what the communities is going to be. Without knowing how it will look, it will be available to every SMT on here.
That said, I do agree with you that it would be great to have a UI that could be used to group content much better and create groups that interact around common topics. I am not sure how such an interface would look but it is a worthwhile endeavor in my opinion.
Just a thought but how about a reddit type interface with a built in chat feature that would allow members to gather around an individual topic and interact with those who have similar likes.
I am not sure of the technical possibilities of something like that.
From what I can make of it, what you describe is what we will be looking at in some fashion.
My understanding of andrachy's point is that these things are more than possible. It just needs developers. This is a blockchain aimed directly at developers.