If you’ve been reading the forum for long, you’ve probably seen many posters describe admissions decisions as random, crap shoot, luck, nobody knows, reach for everyone, and similar. I’ve seen posters claim that nobody has higher chances than the listed average admit rate for their score. So the kid linked in the early example who was accepted to all 5 of HYSPM would have no better than the previously referenced 10% admit rate for high scores at MIT and similar chance of admission for others, meaning that the chance of him being admitted to all of HYPSM would be astronomically low.
I think one of the key reasons for this belief is not understanding the admission process well and underestimating the importance of less visible and less objective parts of the application. For example, assuming a small different in stats is more important than large differences in out of classroom activities, large differences in backgrounds/evidence of positive character qualities, etc.
I agree with CU123 that there is a varying degree of certainty for different applicants and colleges, rather than absolute 100% certainty of decisions for all applicants at all colleges. This is generally how predictions work in any field that has a human component to the evaluation criteria, such as social sciences, as well as many fields with limited human components. For example, a meteorologist might say there is an 80% chance of rain tomorrow, rather than say weather is unpredictable because it is impossible to know the outcome with 100% certainty.