Notice how the right wing people saying the lockdowns caused this are wrong. The lockdowns certainly didn’t help, but this problem has been brewing for far longer.
Yeah, this is probably a chart showing social isolation and living online. Of course that would increase during lockdowns too, but the trend was already there.
Pretty sure you're just naming another symptom that is correlated but not the cause of the depression. Likely the cause of the depression and the isolation is the destruction of third places and the opportunity for unsupervised and unstructured play. Kids spend all their time online because there's nothing else for them to do. There's nowhere to play outside, and even if there is, they're not allowed to go there without adults micromanaging them.