I like idea (1), where kids don’t have mental space to sort thoughts out. Although I disagree that most kids are too busy for it. It may be that habitual social media use decreases kids’ free time, as they use social media/their phone as soon as they’re free, rather than sit, think, and process thoughts.

I think this is also applicable to adults, although it’s effects could be less since smartphones weren’t prevalent when current adults were children.