Well I’ll be the contrarian here; I read this opinion piece and think it is just as junky as Jonathan Haidt’s other work (perhaps you’ll remember him as the guy who claims that Liberals have an under-developed and simplistic sense of right and wrong due to being too hung up on “fairness” and too worried about hurting other people, while Conservatives have a nuanced and sophisticated morality that takes into account a wide variety of values.)
And then Haidt makes his argument in this piece using quotes from Freya India and Rikki Schlott who have made themselves internet famous by deriding “liberal women.”
But this sort of sensationalism is what he has to fall back on because the actual research on the effects of phone use on adolescents typically fails to find more than a small effect at best.