To be honest, I think people over-hype the 'all work, no play' trope about Oxbridge. Of course those towns are not London or Manchester, but then neither is Durham or Bath - or anywhere that is not London or Manchester .
There are some bookish types there, sure, but there are obviously a whole spectrum of 'types.' There is more to uni than just going to large clubs most nights. Would that not get boring after the first term? Students find their own ways to socialise and 'party,' wherever they are. Even if it's hiring punts while off their faces at 4am and then wheeling each other home in shopping trolleys.
My DC did not pull 22 hour library stints or any this type of thing. There are some students who do this, but they are not the majority and not the ones who necessarily get the best grades either. I genuinely can't see how Oxbridge students are any different in terms of their personalities to students at any other uni who got As and A stars at school. Why would they be?
The terms are shorter but, if anything, that's less pressure because they have longer holidays! Also, at Cambridge (I'm sure Oxford is the same), they are catered for (but have their own kitchens too), are guaranteed accommodation for the whole 3 years and have their beds changed for them. They don't have to worry about not having time to go food shopping or finding accommodation. All that 'practical' type of stress is removed.
Honestly, my DS is reasonably bright but no different to an average student at Durham or UCL or any similar uni. Why would he be? Yes he got into Cambridge, but he could just as easily not have. The selection process is hardly a perfect science - they turn down thousands who could have thrived there. DS got a starred first in a humanities subject, but I can honestly say, he has never read a book since he was 12. He did work hard for finals, but in general, he was probably socialising, in some form or other, 4 or 5 nights a week, in his own or other colleges, bars, etc. There are 30 odd colleges which means 30 odd bars, all with their own events going on all the time. It's only 48 mins to London if you really must go to a massive club. But he lives in London anyway - he was only away for 3 x 8 weeks in a year. I just think there is unnecessary hype about Oxbridge when it's no different to other similar unis. An essay is an essay - they can spend an hour in it, or 20 hours. Any degree is what you make it.