To make it even more complicated, majority of those asian kids are either from abroad (not US citizen), or born to wealthy and/or highly educated asian families (due to selective immigration policy).

I don't know how anyone can come up with a racial quota and call it fair.

Because the vast majority of Harvard students are from the USA?

You seem to be suggesting that Harvard should represent the US because it currently does represent the US. I don't find that particularly compelling logic, but I believe the underlying assumption is also false.

Harvard has roughly 20% international students, whereas the US as a whole has about 0.6% lawful non immigrants[1].

[1]https://www.dhs.gov/sites/default/files/publications/Nonimmi...

Colleges do have a significant amount of international students, but the high number is actually in part because they pay more for tuition - it's a good revenue source for colleges. The percentage rises and falls over time for related reasons.

The percentage also rises with higher degrees - people often finish their undergrad in their home country, then go to the US for their graduate degree. But undergrads are the bulk of college student bodies.

So overall, most college students in the US are from the US.