I think its not just kids anymore, it’s adults too. Everyone is glued to their screens these days. But kids are more vulnerable to influences from “social” media and don’t have any defences to the psychological warfare going on. Of course they feel like shit.
It’s not a simple story of just taking away the phone.
And later, after she did take the phone away, she found her daughter had kept all old phone that was supposedly sold.
It does seem to be a pretty extreme case, but there was lots going on here.