I have what I think is a unique perspective on this. Private small self run social media already exists. It's personal Minecraft servers. When I was younger I ran a Minecraft server out of my toaster of a PC. Friends hopped on, made their own little houses, built stuff and talked. Friends would pass in and out and in order to get in you had to be invited! I'd say max there were 10-20 people on there somewhat consiste…
You can’t even send photos with Minecraft though. It’s certainly a social experience but in no way comparable to say, Facebook or instagram like Friendcamp in the article
If I was hanging out with a friend in person and they kept showing me pictures of other stuff in their life I'd get bored pretty quickly. If I'm hanging out with someone, I want to be talking with them and doing stuff with them, not getting a slideshow of their most glamorous recent moments.
Each to their own, I guess, but I find the normal mode of interaction on "social media" (including all that photo sharing and commentary) to be super weird and undesirable.