You guys sure do love talking on forums about how much you dislike/don't use social media
I think the problem is the term 'social media'. That was useful when they were introduced and had to branded as 'new flashy thing!', but it's long since lost any significant distinction from 'media', which of course, is an inherently social construct anyway.
The other part is that it's just regular old friend 'peer pressure' and not really a social platform. How many genuine new connections to people and groups you didn't know about before have you made through Facebook, Twitter, or any other 'social' website? How many actual insightful conversations where you really got something from it?
Don't bother thinking about the number, it's not the point. The point is that you are not more likely to experience actual social interaction through an unfocused website than you are through a focused message board like neogaf here, or reddit, or maybe even 4chan. Sure, they're all echo chambers and they won't teach you anything you don't already agree with, but "social" sites are even less likely to result in that. It's kind of like choosing between CNN and FOX News. They're both trash, but only one of them is full of lies to the point of brainwashing.
If you really want to go all-out and be consistent, you could just go offline altogether. It will probably do you good, since cognition and well-being tend to go up after the initial 'detox' from the addictive online environment.
Personally, I like neogaf. I sometimes do learn something new, or see someone commenting on a cultural concept in another I'd never even heard of. It doubles as a news aggregator (mixed blessing, see echo chamber), has the occasional collective 'yay science!' topic (it is crazy hard to find someone who cares about science in real life, or even social media), and having proper moderation means you tend find genuinely nice supportive people without having to walk into the forest of dicks known as relatives and people you grew up, you never liked, but somehow they added you on Facebook.
So neogaf it is.
The only real issue is that I like taking photos and sharing them. I should probably switch to instagram, but the reality is that none of those sites are really just the service that I want: sharing pictures or events with people I actually like, without any bullshit.
Facebook, unfortunately, has gone full bullshit in recent months where I can't even browse it between all the ads anymore. It's sad, but it's not the service I need, nor inherently require. If you had to pay for it, nobody would be on Facebook today.
