> Ability (not innate, but current) to learn a particular set of things. How well you are prepared, motivated, and maybe even have some innate bonus points.

Again, you have kind of a chicken-and-egg problem here. Ability is typically measured by standardized testing, which is a poor proxy. The same way engineering interviews are a poor proxy for actually measuring engineering ability or ability to add value as an SDE.

Unfortunately, measuring ability this way also captures your socioeconomic status, family stability, medical conditions, and many other things that adversely impact your "ability" to perform well on a standardized test.

We could argue it's not on Princeton or other institutions to account for that, but as a society I think we could probably do better in that regard, by offering a variety of solutions to this complex problem.