I'm not completely on board with this. I do agree that the emergence of smartphones has had an effect on kids, but I'm definitely not going to jump on the bandwagon of "this one thing is the problem and we haven't realized it". 
As an educator, we need to empower students to think and make judgements. I don't think completely cutting off smartphones accomplishes anything. It seems to push away from being information and media literate. 
Making smartphones a scapegoat for our many problems is not the way to go. The moral panic and "but think of the children" is repackaged for 2024 here.