My son is in his 3rd year of engineering at Cambridge. You're right - it IS very pressured. It's a very difficult course indeed. And of course you'll be aware of the fact that the terms are very short so they are extremely intense. He basically works the equivalent of a full working day, has a break for evening meal then gets back to it for another couple of hours. He could do less but doesn't want to be floundering near the bottom of the year group. It's not something that would suit me, and it certainly wouldn't suit my youngest son who applied to different unis (and is now in first year, er, living his best life, shall we say, and worrying me sick 😫). But it seems to suit eldest DS down to the ground. He seems to enjoy the fact it's difficult, wierdo that he is.
It's trotted out all the time, "Oxbridge isn't for everyone." But it's so so true. And that's not a judgement on the people that don't go at all. The most important thing is ending up at a uni where the young person is happy and thriving and making the most of their talents. I do feel that DS is naturally very "Cambridge". He is very able, very confident and extremely determined and ambitious. He's always said he doesn't feel particularly nervous going into school exams, as he knows he's good 😆and he's always well-prepared and he's taken that attitude with him during his uni exams.
DS did really well at his ENGAA (I hear this is called something else now) and took the interviews he did in his stride (relatively), understanding that apart from academic ability, they're looking to see if you're teachable according to their teaching style and can pick new concepts up quickly and apply them to a problem yourself, even if you need a suggestion or 2 from them. I think they're probably well practised at recognising he natural talent in people, seeing past ordinary nerves, and recognising a level of nerves so bad that it might indicate a bit of a difficult time coping with the pressures if they did get in.
His girlfriend (on another course) is also very similar in personality, however she feels the pressure quite a bit more. They both feel that they would have had an easier ride elsewhere and been able to enjoy more free time than they do now. Don't get me wrong they still have fun, go to parties and the formals and balls etc. But really it's all about the work and keeping up with the workload. Which I guess is a big adjustment if you've always breezed through school. And it's hard if you come down with an illness.
Ultimately, you're exactly right, water will find its own level. I hope your daughter ends up where she is meant to be, whether that's Cambridge or elsewhere.