It’s talking about parents giving 1 year olds and 2 year olds 1-4 hours of screen time a day. That amount of screen time for developing humans who sleep for a substantial part of the day is most likely poor stimulus in my opinion. I don’t see how you are jumping to parents prone to producing developmentally delayed children. You call nature. I call nurture. But just to check, which parents are more prone to producing children with developmental delays?
When’s the last time you saw an engineer doing tensor calculus? And that said, whomever said Einstein wasn’t good at math has also never done tensor calculus.