None, never had out of principle (except for research purposes, never personal)
Indeed, that is insane.
I believe social networks have ruined internet.
It may be counter-intuitive, but in reality it’s huge move against freedom, and i’m pro freedom.
Social networks are gigantic human anthill created for anything but freedom: manipulation, profit, harvesting of personal data (which most people gave up voluntarily anyway) 
Anything ‘social’ oriented is a bad idea to me, especially if you think about the goals of those networks.
I have a very old-school, hacker / cyerpunk notion of internet of 90s, maybe even something like A Declaration of the Independence of Cyberspace
I use only forums like this one, to connect with more than few people when i feel so. 