Conservative lawmakers have also done their best to attack the policy. During one speech during a debate about quotas, Senator Flavio Bolsonaro — the son of the former far-right president, Jair Bolsonaro — asked, “What about poor whites?”

Whataboutism runs in the family, uh.

That said, there are also quotas for those. For example, I'll coarsely translate an excerpt from Paraná's Federal University's site:

Thus, there are four quota groups:

1. Public school students, regardless of income;
2. Public school students, with household income lower than 1.5 minimum wages per capita;
3. Black [pretos], mixed [pardos], and indigenous [indígenas] students, regardless of income;
4. Black, mixed, and indigenous students, with household income lower than 1.5 minimum wages per capita.

Relevant to note low and mid-low classes study almost exclusively in public schools.

Some anecdote. My uni (the above) implemented quotas in '05; by then I was in my first grad, so I remember it well. Criticism sprouted from all sides, including black people - like one student saying she was glad she was admitted in '03, so nobody would think she did it "through the backdoor" (pela porta dos fundos).

To be fair with her, back then nobody actually knew how it would turn out. Two decades later, though, we see the quotas help by a lot.

It's also relevant to note that, in Latin America, racism piggybacks on classism; while in Canada and USA I feel like it's the opposite. In other words, I think the primary source of prejudice here is social class. This should explain where both Flávio Bolsonaro's "whataboutism" and that student's comment come from.