This seems to have slipped through “Can Naked Kids be Art?” fiasco without notice.
Associate Professor Robert Nelson (Monash University) has sold out middle-aged men: “This was a photo taken not by a middle-aged man but the mother of the child. It seemed quite a responsible thing to do.”
He could be just reflecting social norms though. Qantas, British Airways or Air New Zealand have a policy of not seating adult male passengers next to unaccompanied children.
A few years back a male friend almost landed an assistant position at a kindergarten. The position was withdrawn at the 11th hour when several parents complained.