[iClaudiusX]

| social on their own terms

I think that is the key insight. Phone calls and instant messaging before smartphones meant that you had to make a deliberate choice to be available at a given time, and to give that communication most of your attention. When you wanted to stop, you simply logged off.

Now there is the expectation that you're always online so nobody wants to be the one to "bother" everyone and interrupt what they're doing. And you're constantly reminded of what you missed out on with the endless feed of everyone else's messages to each other.