This is not caused primarily by "screen time".
It's been caused by the mass eradication of third places for young people in basically every city over the past three decades - and a society that's hostile to the concept of teens socialising in public spaces.
www.theguardian.com/politics/liv...
‘Worrying’ levels of screen time means young people losing confidence to socialise in person, minister warns – UK politics live
Culture secretary Lisa Nandy says ‘majority of young people spend all, or almost all, of their free time alone in their bedrooms, online’