The mistake is thinking that there's some objective and correct way to measure eligibility for these finite spots. The reality is much more complicated; there are way more people who would be successful at an Ivy League school than there are slots available for those people. Whoever you pick, every one of them will kick ass, so it's not really about making sure everyone is qualified, it's about making sure the people who are qualified for your school and not qualified for other opportunities (because racism, caste) get their shot.
The whole point is finding the qualified people for whom this is as close to their only shot as possible, and giving them that shot. Poor minorities are more often those people than wealthy white kids, because the white kids will land on their feet.
The poor minority kid might be the first in his family to go to college, might have only had enough money to apply to one or two schools, and if college doesn't work out for them, they're basically screwed.
The poor minority kid might be the first in his family to go to college, might have only had enough money to apply to one or two schools, and if college doesn't work out for them, they're basically screwed.