Good point. A lot has been written about the sociology of the English public school system. I don't know enough about it to comment with any confidence, but I gather that a very distant style of parenting somehow became part of British upper-class culture. The frequent absence of fathers was particularly noteworthy. During the heyday of the empire, of course, in the social classes that populated the public schools, a lot of the fathers were out for years at a time civilizing the world (or dead, casualties of the same mission). Boarding schools probably had a stronger rationale then than they do now.
I've only known two families that sent their kids away to boarding schools, for good aspirational reasons in both cases. (Family tradition also played a role in one case.) But I suspect that there's enough of the negative stereotype in play as well to make a difference: some socially elite parents don't have the time and interest to raise their own kids, and they park them in boarding schools to get rid of them. A propensity to homosexuality might well be one response to parental abandonment.
In any major city today, there are enough excellent prep day schools that I would question the decision to board a child. By the same token, many of the traditional boarding schools now accept day students as well. None of this applies, of course, to extremely remote areas where boarding is necessary because there simply aren't enough kids within 200 miles to support a reasonable school.
I boarded for a few years during the early 70s. wild times. We were too focused on sneaking into the girls houses at night to consider any perverse alternatives.
my younger boarded in PA and they used to meet the girls on a adjacent golf course at night.
when you don’t have a car to neck in - you make do with a letterman’s jacket and sweater to keep the dew off your date. Just don’t forget when the sprinklers come on.