Again, not everybody thinks the same. It is possible to prefer a non-relationship to a superficial relationship. Some people value authenticity for its own sake.
I'm not trying to convince anyone to change their mind, I just want to explain why the appeal of the social media is not universal (not that it has to be of course). For example there are some people I would call "intentional introverts" who quite genuinely would prefer not to have a happy birthday greeting from someone they are not close to. Others obviously are delighted by the same thing. It takes all kinds to make the world, etc etc.
followed by
What's not to like?
Dude, I think you answered your own question: superficial relationships masquerading as genuine ones - you know, that does bother some people.