The kind of person who doesn’t believe this is bad for children, is the same kind of person who would believe Big Tobacco sponsored studies about how cigarettes don’t cause cancer in the 80s. For the data driven like yourself, I remember a Jeff Bezos anecdote, “When the data and the anecdotes disagree, the anecdotes are usually right"

Try spending time with a phone addicted teen and you might have a more sympathetic take.