We need better alternatives, but I think people overestimate what a "better alternative" would look like. That whitepaper from a few years back about building a social network on top of existing email infrastructure comes to mind.

A bunch of my friends don't use Facebook. We exchange long emails regularly instead. It's awesome. Solves the problem Facebook supposedly solves much, much better. And I think it would be enough to replace Facebook given a few extra features to abstract away, through a user interface, stuff that email can already do.