And even then, being excluded from having normal access to a phone still isolates them from "normal" people. Everyone pulls out their phone and all the phoneless person can do is either sit there in jealous silence like a loser or try to get everyone to stop playing on their phones when they're around them (also like a loser).

Overall not an ideal situation.

I have to disagree. There was plenty of bullying and isolation for kids before social media, before the Internet and, I'm sure, even before the printing press.

Kids can be very cruel to each other. This is (mostly) due to an understanding of the world that only includes a limited understanding of cause and effect.

That's not new, nor is it particularly profound. And it has nothing to do with computers or "social media."