The entire context of this thread, set probably inevitably by the contents of the OP, is that 'top universities' equal Oxbridge (occasionally Durham gets a name check, or the phrase 'other leading universities' or the evergreen 'RG universities). In reality, the fight back against institution blind recruiting tends to be a much wider one, very broadly drawn as old universities > new universities. This sits within the wider common MN trope that Oxbridge is the ambition of all the most able students.
But to meet your request, examples of Oxbridge exceptionalism (and these are drawn from posts from people on either side of the debate):
All degrees are not equal, especially when you consider and compare eg the tutorial system at Oxford or the similar system at Cambridge vs other universities etc,
My firm recruits university-blind and have people on the graduate scheme from many different universities. The ones from Oxbridge often stand out academically
I don’t think that many posters realise that Cambridge and Oxbridge produce fantastic graduates because they demand much more of students, particularly in humanities subjects
I think academic types choose Oxford and Cambridge for the challenge and the cache not the job prospects
nothing compares to the preparation provided by engaging with the Oxbridge tutorial system for three or four years
Oxford and Cambridge students tend to stand out anyway....