@delilahhey the thing is, accommodation and food are non-negotiable, and are considerably cheaper at oxbridge.
All the other things you mention are very much discretionary. DS1 is in his second year and has done none of them except the ball (which was admittedly v pricey, but in no way compulsory). Definitely no ski trips or secret societies (although I suppose the whole point is that I wouldn't know... 😂)
The whole Cameron/Johnson Bullingdon Club bollocks has done so much damage. (Entirely their own fault of course.) I was rejected by Oxford but had an interview and was so intimidated by the serried ranks of public school kids. My brother went and his social circle was all children of titled gentry and Cabinet ministers. 30 years later I have been genuinely surprised by how socially ordinary it is now when I've spent time up there seeing DS.
He knows a couple of public school people I think but most of his friends are just absolutely bog standard kids from bog standard schools, and I say that with love and respect having been one of those kids myself and having produced two of them. Just totally ordinary, normal young people who happen to either be very clever in one subject or get a bit lucky with the selection process - in the nicest possible way, I wouldn't say the ones I've met are even unusually clever, although I'm sure there are lots of unusually clever people there, as there are at all good unis.
Oxford is not full of braying Sebastians these days and, just as importantly, it would be possible for someone on a tight budget to go to Oxford and spend a lot less than they would at any other uk university (unless they're Scottish and don't have to pay fees) because housing and sustenance, the two biggest line items in most student budgets, are so heavily subsidised by the colleges. Any young person for whom budget is a serious consideration should be aware of this and I think it would be a real shame for people not to give it a go because they think it's full of people from a different planet. It used to be, but it's not now.