Then you miss out on the social discovery aspect which is a key part of social networking. You're just avoiding the problem of where to go by cutting off your own legs.

Seems contextual whether that's good or bad: one theory of sleep is that we lose consciousness so that we don't go out and get ourselves killed in low visibility conditions.

Social discovery is obviously something people want or they wouldn't use social media services in the first place. Pointing to the existence of other contexts where that doesn't matter is neither relevant nor insightful.

It's like saying 'why worry about these problems, just don't don't use the the internet at all.' I still like paper books and other things and usually spend a day a week off the internet but that doesn't help anyone who's trying to solve an internet problem, does it?

That's a rather simplistic model of how Twitter works. People use @ replies and hashtags for impromptu communication between strangers.

It's not how email works either.