> Today a 13 y/o boy can see more breasts in an hour than every one of his prior-digital age male ancestors have seen combined.

May be true on average, but there are not-so-exceptional exceptions to this. For example areas where topless sunbathing is common and cultures where breasts aren't hidden because of puritan ideas. (Also maybe Nordic countries? Not sure how old teens are before mixed naked saunas are a normal thing) If that was a significant problem you'd think we'd see some extreme behaviours there.