A Harvard, Princeton, and Yale alumni survey found three-quarters live in zip codes that rank in the top 20 percent by income and education. Half live in the top 5 percent of zip codes.
Only if your only criterion for success is diversity. I don't think the intention has ever been to recruit evenly from all zip codes or whatever. My understanding is that the idea is to have a substantial portion come from a less advantaged population. (Heck, these universities still need to have a lot of wealthy kids so their families give them lots of money. A dozen self-made millionaires aren't worth much compared to a handful of trust fund billionaires.)
If I flip your numbers around, it actually sounds pretty good: a full quarter of the alumni come from the bottom 80% of zip codes!
What would the counterfactual be? The population of elite New England boarding schools, at least in 1934 when the decision was made, was pretty solidly top-1%. (It too has diversified recently because of efforts by those top prep schools to accept diverse applicants on scholarships, but a major applicant criteria they use, particularly for underprivileged applicants, is...get this...the SSAT!). If they're accepting 25% of students from outside the top 20%, that is way better than the situation 100 years ago.
> Students without parents that are college graduates are also at a disadvantage no matter what their potential is.
It is possible both for SAT scores to predict a person's potential to contribute in cognitively demanding fields AND for there to be a strong correlation between SAT score and parental income/zip code/etc. In fact, this is true even of a theoretically perfect measure that can somehow peer into the future of every prospective student were they to be admitted.
Is there some reason you expect that the children of people who did not go to college will have the same level of potential as those born to college graduates? Would this hold true of the children of professors, or Nobel winners? Is there any place for 'nature' in your worldview, or is it purely 'nurture'?
So their efforts didn't work.