We've known for a long time, and I think culturally we've accepted, that diversity is an important thing in the work of knowledge.
In the university library, we know when a book has been used in a class or put on reserve... or while it was out, did somebody call it back in. It turns out to be a pretty good indicator of how relevant the work is at that time.
The degree to which campaigns have become dominated by marketing is breaking the spirit of democracy, and we're all just so sick of it, across party lines.
How your social network - the people that you know, or in your community - understand or value a work can be... a tremendously relevant indicator of how important or meaningful it's going to be to you.
In the digital age, we filter forward instead of filtering out. As a result, all that material is still available to us and to others to filter in their own ways, and to bring forward in other contexts.