The problem with this approach is that you are attributing the success of this person, almost exclusively to their 4 years at an undergraduate institute.  Let’s say a person who went to Harvard as an undergrad wins a “Nobel prize”. What does that really tell you about Harvard? Do you really want to make an argument that the four years at Harvard are what “made it possible” for this person to with the Nobel prize?
Causation does not equal correlation. It would be very hard to measure how any undergrad education contributed to  that success. Attributing all of that success to the university is just silly. Parenting, perseverance and personality have probably more to do with the achievement of a student than association with a university.
Also, a student who is good in physics and wanting to pursue physics, in all probability seeks out schools that are “reputed” to be good in physics. How does a school get a reputation of being good in physics? Well spend “Money” to acquire great profs, labs and use them to do research and publish. In short, whether you get good at something in higher education, is increasingly determined by how much money you are willing to throw at the problem. It is not a sufficient condition, but it is a necessary condition.
So the rich well endowed school that finally landed this student benefited from selection bias. He then goes on to win a Nobel prize. So what? The only way you can give the school the credit is if you can show that “this student” would not have won the Nobel prize, if they had gone to “Podunk state University”
You can fool yourself into believing that “Output based rankings” are “more accurate”. They are just the flip side of the same coin, whose other side is “input based rankings”.
All of these metrics, whether input based or output based are proxies for measuring parental and institutional wealth in some way or the other.
What these rankings really tell me is that “its good to be born rich, and go to a rich school. If you are not born rich, try to get admitted to a rich school”
Given that, there is no need to get all twisted up about any one ranking. You don’t like one, try another. You don’t like any, do your own.