Though I would mention that the results were virtually in line with each other. For HYPSM, an unhooked applicant nearly has to be a unicorn. For Oxford and Caltech, they would have to be one of the top students in that subject in the world that year.
For U of C ED, UMich, and UIUC CS+X, being merely exceptional is enough.
The good news (IMO) is that there is essentially no difference in opportunities/outcomes regardless of which of the U of C/Caltech/MIT/Oxford you go to (UMich and UIUC offer a lot of opportunities too but they are more gigantic so you have to be more of a go-getter).