Facebook alone has over 2 billion users, and keeps growing. I can't see how it is a bubble that has burst.

I've met many people in developing countries that don't have running water, or indoor sanitation, but still access Facebook through a cheap smartphone. It's important to a great many people.

Personally I find Facebook extremely useful; I just hate the implementation, which seems to be a buggy mix of dark patterns which attempt to manipulate my state of mind and do bad things with my personal data.

A realistic open competitor would be extremely welcome, but first you have to somehow get past the network effect.