Talking to eye doctors now, they are saying it’s an near-sightedness epidemic in kids. This is not a large sample of experts but both in person and from the news. One problem I think is that they hold the screens really close, and they dont take breaks to stare at infinity often enough (Max 25 min straight for children was the instruction I was given). There was also something with the eyes of small kids being much worse affected than adults. My ophthalmologist told me there was now 10 kids in each class that need glasses in first grade, up from just 1-2 before screens. That to me sounded pretty bad.

Depends on the class sizes - I would expect variation in there. With 25-30 in the 90s I recall there being at least 4-5 in a class commonly. Without context that doesn't say much other than it stood out.

That isn't reliable - statistical literacy and especially /native/ staristical literacy is shockingly rare and this is exploited constantly by people with agendas. People think crime is on the rise when it is at historic lows and 1st World Pollution in the toxin sense is getting worse when it has gotten better in many ways.

(The Environment is always a multifaceted thing. Is it better or worse for a vast desert to turn into a monoculture forest? Nonbiodegradability is a bad thing but it technically does sequester some carbon. Still air without lead in it is far better.)