sendsummer - I do not all see the logic of your last point. What is to stop any boarding school making use of external and/or part-time staff in order to extend choice? Radley could access a similar group of local talent as does Abingdon, in order to extend choice, given that it is just down the road.
Also, there are many ways of getting the positives of good coaching, a winning mentality and also team values, without putting people at the risk of head or other injuries, or making violent collision with other kids a core elements of a sport. Most such sports do not also have, in the position of a lead role model, an England captain with about a year of bans for diverse acts of violence and verbal abuse.
I think compulsion remains a serious issue, though if a kid has genuinely enjoyed playing the game at a prep or junior then it's clearly not a problem. But at Radley, as 1805 put it so very well,
"Some of the boys had no interest or enthusiasm for the game at all, and they survived just fine."
So why are they being forced to play? Did their parents every actually ask them if they wanted to do this? And why for that level of fee income is "survival" the metric on things being OK, when positively enjoying a sport ought to be the outcome. My son "survived" junior school rugby, but we moved him to Abingdon so he could choose what he wanted to do and get some real enjoyment of sport.