Fundamentally, all social medias have two purposes:

1) Connecting with family and friends... for me, messaging Apps already solve that.

2) Curating new, exciting and relevant content.

What I always find interesting is that most projects try to solve 2) by building a platform that is exactly like the competitor but "decentralized".

If such a system instead runs entirely on the users device the curation could even use data such as browser bookmarks or history without infringing massively on privacy.