So certain people are constantly trying to “crack the code” of Ivy/T20/whatever admissions, meaning in some way figuring out the “secret formula” that these colleges all use to score students, but refuse to tell us.
But there really is no “secret formula”, and we know this from both what AOs say and in fact what we learned in the Harvard litigation. Nonetheless, some people refuse to believe that and keep trying to figure it out.
As part of their endless effort to discover the secret formula, the people on that quest do things like look at various statistics and try to convert those into a formula. But very often all they are really looking at is a statistical correlation, not an actual example of a causal formula.
And I would gently suggest your observation about many (not all) Ivy admits being top 10% in their respective classes (among high schools that rank) is really just a correlation.
Again, we do know these colleges generally like their applicants to have challenged themselves across all the core areas, and to have gotten very good grades (some people sometimes say “near perfect” grades, which is one reasonable way of capturing their normal standards).
OK, so then people who do that are usually going to be top 10% in schools that rank. Meaning they’ll have the grades, and if necessary the weighting, they need to be top 10% in most cases.
But suppose that only 5% at some high school in some year have taken the courses and gotten the grades that these colleges are looking for. Do you think they will force themselves to consider 5% more who haven’t done that? Of course not.
But then suppose at some other high school in that same year, 15% have taken the courses and gotten the grades these colleges are looking for. Will they force themselves to cut 5% anyway?
This is really the same question, and very likely the answer is no. As long as you have taken the courses and gotten the grades they are looking for, they are very likely going to consider you. And if that is 5%, 10%, 15%, or whatever at a given HS in a given year, they won’t care, because why should they?
So like others, I really think you need to start focusing your energy and effort on the things that actually matter. If you obsess over these secret formula issues, you are very likely only going to be making yourself anxious for no good reason, and anxious people often do not perform optimally. In terms of academics, you know what you actually should be doing–challenge yourself across the core areas and do as well as you reasonably can.
And then you can apply and see what happens, like all the other kids who have done the same across all the many high schools where people will be applying to this same handful of schools.