So many qualified people out there, so many get rejected

INTEREST: As a student interested in education, one thing that struck me as I read the article was the constant and unwavering belief in the elite and unmatched level of intelligence at Princeton University. Patton describes Princeton women as "brilliant, resourceful, very well-educated," who have "almost priced [themselves] out of the market."
She further claims that "there is a very limited population of men who are as smart or smarter than we are" and that no Princeton woman will be "never again be surrounded by this concentration of men who are worthy." She continues by saying that not many men met outside of college will be a Princeton woman's "intellectual equal" and further describes Princeton men as having a "soaring intellect." So what bias is there in an Ivy Leager's mind about the supposed superiority and intelligence of alumni of the college they attended, and is it at all founded?

INTEREST TO TOPIC:

Are people who go to extremely well renowned colleges like Princeton truly on average much more intelligent and smarter than others?
But we still need to clarify what intelligence and "superiority" mean. Patton often uses the term "intellect" and "intellectual," along with "brilliant" and "resourceful."

A MORE FOCUSED TOPIC and QUESTION:
I've also been thinking about admissions processes recently, since the Class of 2017 just got admitted: so the question that arises here is "Does Princeton admit the most intelligent people who apply to the class?" "What are the metrics of intelligence used to evaluate 'worthiness' of attending Princeton, and do these metrics justify the beatific claims Patton makes regarding the intellectual superiority of Princeton men and women?"