At its core, this examination is able to distinguish students who put in the effort to ace it. No one is inherently better or worse at this exam. The only thing that makes some students do well and others fail is that they were not able to or not willing to put in the time and effort. This exam is colorblind, need blind, and completely unbiased.
We have to remember that the population that takes this exam and aces it is also a disadvantaged community. Most of the students who gain admission to these elite high schools fall below the poverty line already. More than 75% of them are first or second generation immigrants. Many will be the first in their family to attend college. The population that enters this school is not one that is privileged. It is one that works hard to achieve results.