Steemit already has subcategories which act as a filter; for example, "homesteading"..
Filtering the content should be automatic. With current tags there aren't anything automated, users have to make an effort to find and see everything that is posted with a certain tag. Users can't even subscribe to a tag.
So I disagree with you because growth trumps your complaint ... And your complaint can be fixed without sacrificing massive growth...
On the contrary, I think it will be absolutely necessary to fix the UI/UX if we want to have millions of users. With the current UI the experience will be so bad that the system will become unusable and old users will leave and new users won't join.
"Filtering should be automatic "
Yes, that's what I mean. Fix that. Problem solved... Growth continues...