Unfortunately, parental income can be a terrible proxy.
High income doesn't necessarily indicate wealth or high class. It usually indicates highly educated, high level working class, like doctors and software engineers.
Families with generational wealth often have very little direct income. All wealth is in assets that they borrow against, which doesn't count as income. Even when they take income or realize capital gains, they often do it erratically, so it can be fairly easy to game a university admission that looks at parental income by avoiding income for the years universities request.
Meanwhile, I know people whose parents had very high incomes, but didn't actually have any real, accessible wealth saved, didn't save for their children's education, and had slept walked into too expensive of a lifestyle to divert any of their income.
Because their parents made too much, they got zero financial aid and ended up covered in mountains of loans because their parents didn't actually have the money to give them.
To be fair though, the fault in this case lies exclusively on the irresponsible parents who had the option to provide for their children's education, but opted to leave them to the wolves.
Parental income is a terrible proxy? The abilities of ones guardians growing up is a huge factor in what opportunities someone is offered and a lot of that is dictated by how much money is available for the child. Other aspects like the intelligence, love, care, wit of the parents and child may be larger factors, but that's not something one can quantify on a form.
My oldest will be applying to college in 2027. If it would maximize their chances of admission, I could arrange for my 2026 income tax return to show any 5 or most 6 figure sums that I needed. If I really needed to, I could do the same for 2025 as well.
Showing a household income of $75K in that year/those years won't change the more comfortable financial situation they grew up in.
Brilliant and accomplished people don't always pursue wealth. In certain subcultures it's crass, uncouth, one might even say low class to pursue something too practical or employable, to be too interested in material things and conspicuous consumption. These people aren't rich on paper but they are rich in genetics, habits, attitudes, values, vocabularies, media diets - and they raise brilliant, accomplished kids. Affirmative action for high academic performers subject to low family income would be an almost perfectly tailored handout for this cohort.
Filtering on parental education level might knock most of them out & get better at targeting kids who outperformed their circumstances in more surprising ways. But is the legibility or surprisingness of the kid's outperformance really the point? I think maybe what you'd want to do is give some slots in the meritocracy to kids who are not outperformers at all, but chosen randomly, without regard to academic performance.
For wealthy people, the listed income can be arbitrarily changed if there is a motivation to do so. If having low income benefits their kids admissions to Harvard, then this year the family business will issue no dividends and rather just loan money to the owners, and the CEO compensation will be temporarily adjusted to $30k/year.
I assumed by class they were speaking about the delta between doctors/software engineers at Amazon and warehouse workers at Amazon. I assume generationally wealthy families applying to colleges are already identified by admission departments and their less qualified children's admission is (and would remain) predicated on donating to the library fund.
High income doesn't necessarily indicate wealth or high class. It usually indicates highly educated, high level working class, like doctors and software engineers.
Families with generational wealth often have very little direct income. All wealth is in assets that they borrow against, which doesn't count as income. Even when they take income or realize capital gains, they often do it erratically, so it can be fairly easy to game a university admission that looks at parental income by avoiding income for the years universities request.