This from researcher Amy Orben on children and use of tech sums up my reading of the evidence.
Nothing to see here.
All effects tiny and confounded.
Like almost every tool that humanity has invented from fire and the hammer to computers and semiconductors. Technology can be used for good or for ill. Humanity has the capability to be addicted to many things, we also have the capability to transcend.
However, the overall opportunity cost vs other activities is a real thing. In essence that boils down to better eating, better exercise and play, time spent with family and community and better sleep.
Eat, move, sleep and play.
Applies to adults as well as children.
Also Jean Twenge
And this Nature Review:
Fears over the effects of digital technologies on people’s mental well-being are forcing social-media companies to change, even if the evidence remains sketchy.