Good grief!
OP do you not realise all the fun stuff they get up to in a good boarding school? It's like daily sleep-overs with mates and loads of optional group activites like making dens and crafts/cooking.
Depends on the kid, of course, but most normal/social (not overly shy) kids who WANT to go will enjoy it and do well.
Our 3 went at 9 (going on 10) as that's the normal age to start boarding for prep school.
Some started a year earlier but any later means you will have missed the main intake and friendships will have already formed. (So best to all start together like at uni with freshers week?)
We were living abroad at the time and moving every few yrs so the childrens' schooling and friendships would have been badly disrupted. (And classes small/friendship options limited.) Therefore, we decided it was better for our kids to go back to the UK and get settled into a school/the UK education system ... and hopefully to make lifelong friends. (Which they did.)
Our company paid most of the fees so it was affordable for us. (Otherwise would not have been.) So for us it was a massive perk which we appreciated!
As we were so far from the UK, there was no "day pupil" or "weekly boarder" options for us - it was all of nothing. (And we thought it would be fine.)
It WAS fine but, of course, we were a bit worried when the 1st one went, just in case we had misjudged the situation and in case he was unhappy when we left him there alone.
But it all went perfectly, as there were all the others there for the 1st time with him. (Group experience!) Not like turning up alone where everyone already knows one another.
Mixed sex school. Quite liberal. (Puppies in the dorms. Small dorms with your own corner area/desk, own duvet covers, possible to decorate your desk area, TV and toast/cocoa in in PJs and duvets on the carpetted floor in housemother's flat on Sat nights.)
It was a BIG adventure (Enid Blyton hol style) for them! In fact at one point (having sent the 1st child away who then came home for the hols and told our other 2 how exciting it all was) we were worried DH might be made redundant and that we would no longer get the school fees paid. So we vowed to send the 2nd child anyway, having prepared him to go, even if the fees would be coming our of savings, as he would have been really upset/disappointed if he had been told he wasn't going. (In the end, no need. No redundancy.)
I do think it's important to say that our kids always knew they were going to boarding school ie years before they actually went. So it was seen as normal for them and something to look fwd to.
They also knew other kids who went away and saw them coming back for the hols. (Though other kids went to other schools of course - but it didn't really matter which school it was.)
So it wasn't a case of surprising them one day and them being suddenly being packed off/banished. They were fully aware and prepared and looking fwd to going! (Like going to uni?)
So if you feel the boarding school concept is awful, just don't send your kids there?! But lots of the parents I met whose kids were boarding together with ours, had boarded themselves and had fond memories of it all! (Even at the same school!)
Boarding schools also have longer hols than state schools as there are often lessons on Sat mornings. So that's nice for parents who want do more in the hols/travel with their kids.
Also there is a culture of doing lots of different types of sport and of being very active, with limited TV & reading in bed very much encouraged. All good. So kids are far more active than they might have been at home (with busy parents) and less prone to becoming overweight, esp as meals are at fixed times.
The school house staff need the kids to burn off excess energy before bedtime so running about and playing ourdoors is very much encouraged. And if you start young an continue this, good habits develop?
Of course, not every kid likes team sports or cross-country but you will be outside playing games, roller bladeing etc, and just going to and from the dorms to the canteen and then to various lessons/activities will mean a LOT of walking/running which is good for the kids?
Not to mention the superior music and art facilities. And much more time to fit these things into the school week if kids are not going home every night.
It's just VERY expensive, so not everyone can afford it. But otherwise what's not to like?!