Turns out if you define a third of your pale population as "Latinx" instead of white, very few white people remain.
Even the 2020 census had the sense (heh) to finally drop the "Hispanic race" and have it as a separate label, but the "researchers" felt like going out of their way to redefine it as a "race" again. Not sure why race is even treated as a scientific thing to begin with in their census, but such is the Amerikkkan way I guess.
Edit: don't even want to think about the causes of this "age gap"
Do you mean they have those options as a response to the race question? Or as a question separate from race? Cuz if you mean the latter, then those are the same options given in this census