If you wanted something equivalent to usenet to come back, you'd have to solve the moderation problem across a number of incompatible governance frameworks, which can not be done in a single hierarchy, no matter how hard you try.

Having multiple moderators of content, and multiple dimensions of moderation (think tags with attached scalar multipliers) could possibly work. Each host of the feed could then just not store anything that fails to pass as legal in their jurisdiction, or fails to meet their moderation policies.

Regardless of its arrangement, any large cooperative collection of stuff, albeit in a feed like usenet, or forums, or a files store, multidimensional ranking/moderating/reputation management is the way to go, IMHO.