Just because you know the relative size of each cohort doesn't mean you know if a specific person was in one or the other. There's always the possibility that someone admitted for money actually ends up excelling. I know quite a few people that got far more serious in college and ended up doing quite well even through in high school they were far from good students.
That's before even considering that some small amount of what graduating from one of these schools conveys is a high likelihood of having networked with other people that will be well placed later. My naive expectation is that someone graduating with a science major from MIT might have had a harder curriculum than someone graduating from that same major from Harvard, but I also (again, naively) expect that the person from Harvard may have made contacts with people that will be more diversely placed and in more powerful positions later.
That's before even considering that some small amount of what graduating from one of these schools conveys is a high likelihood of having networked with other people that will be well placed later. My naive expectation is that someone graduating with a science major from MIT might have had a harder curriculum than someone graduating from that same major from Harvard, but I also (again, naively) expect that the person from Harvard may have made contacts with people that will be more diversely placed and in more powerful positions later.