Nice and well documented article.
As for your questions, as always, it is not all black or white.
Yes smartphones are useful for connecting people, I couldn't just write this comment without a smartphone.
And yes, it is a bit frightening to see all these teenagers (and people) always eyes on their smartphone. In the bus, in the subway, in the shops, everytime they have 2 minutes actually.
They just don't look around anymore.

You can't do much about it, because it is free will.
In the end it is up to everyone to ask him/herself : what kind of life do I want ?
A real one or a virtual one ?