For the reasons outlined in my post I believe that it is hard to show specific causal claims which relate overuse of mobile devices and especially social media to specific problems. Although I think for some specific cases this could still be reasonably inferred.

Just to be clear, the evidence seems overwhelming. This is not some novel research field, but this questions has been researched for long enough to have been pretty conclusively answered.

>1) I've yet to see evidence that the medium is the problem,

This is not relevant to the claim. The claim is that the specific usage pattern of young adults is harmful to their development.

>I'm not convinced that these social media bans are solving a real problem.

I largely agree.