There's a reasonably good overview of some ideas about fixing the harms social media is doing to democracy here and it's well framed by history.

Much of it appears to be a synopsis from the perspective of one who's only managed to attend Pariser and Stround's recent Civic Signals/New_Public Festival.

There could have been some touches of other research in the social space including those in the Activity Streams and IndieWeb spaces to provide some alternate viewpoints.