Obviously, the protective clothing is absurd. Japan is not alone in wanting the schools to act "in loco parentis." (In place of the parent) Double incomes are almost mandatory for folks these days, and the parenting time and skills suffer enormously.
And yes, I grew up when mercurochrome was the remedy of choice; that, or the soap scum from the brown soap for the kitchen sink ?American Family? that had congealed on the bar. This was spread over the cut...lye soap, I think...then bandaged with gauze and adhesive tape.
But then, I was the only boy child, and youngest of three children, of a career 3rd grade public school teacher in Chicago. If my mother didn't see blood or bone protruding through the flesh, I went to school.

And it had to be a LOT of blood. If there was a problem at school, it WAS NOT the school's fault.
I try very hard not to get wroth at things humans do these days. But the danger I see to children comes from abuse, neglect, and ignorance of parents in dealing with their children. What infuriates me is that it is a learned social trait, with the abused becoming an abuser, or often, the victim of abuse seeking out others who will abuse them as they were in childhood.
And I don't see a remedy, nor a social mandate to seek one.
But if I were God for a week, say....there would be innumberable piles of dust where once stood an abusing spouse or parent or boyfriend.
Kis
TheWrathful