Sure, it's an uncomfortable thing to say, but I hope we're not dismissing hypotheses because of how they make us feel.
More to the point - I agree with the comment above about how the term "racist" (and "white supremacist") makes people have fairly strong emotional reactions, and we'd probably have better discussions if we somehow avoided those words. But I hope we can move past them and analyze what this theory is saying to see if it's true. As a wise man once said: "If a statement is false, that's the worst thing you can say about it. You don't need to say that it's heretical. And if it isn't false, it shouldn't be suppressed."
So let me make an analogy. You and I both pay taxes to the US government (or so I assume), which on occasion does some pretty unethical things (cf. "We tortured some folks.") We also both benefit from living in a country that's so powerful that it can get away with unethical things; such a country also gives us all the opportunities in the world. We could object and refuse to be "collaborators," in one of several ways, whether by just arranging our work situation so we don't pay, or moving to another country, or whatever. But we don't - so we are choosing to be collaborators!
But no one really faults us for not doing so - while we all understand that if it weren't for the collective tax payments of all US taxpayers, the US military couldn't commit any war crimes, we are happy to say that the individual culpability of any tax payer is negligible.
And nobody really says that we're stripped of agency and our success isn't our own simply because we chose to e successful professionals in the US, even though if you dropped us into the median country, we'd certainly be less successful.
On the other hand, that doesn't mean that we don't care about not doing war crimes, or about the good of other countries! We, collectively, the taxpayers / voters, ought to hold our country and especially its military to a high moral standard, and ought to admit wrongdoing (and make restitution, where possible). If we fail to do that, it's a shame on our country. And we the taxpayers / voters need to ensure that the US is not what it is at the expense of other countries, and even above that, there is bipartisan support for foreign aid.
If we're comfortable with all of the above, and we don't think that anyone is making "f--ked up" claims about individual American taxpayers when they accuse the country of having committed war crimes or anyone is impugning the agency of individual American professionals when we call America the land of opportunity, I don't think we should shy away from analyses of the "model minority" that would say that collectively, across society, improvements could be made.
(And, as a child of Indian immigrants to a deeply segregated town in the South, I have seen first-hand that the rational thing for non-white non-black immigrants who care about their success and their children's success is to assimilate into the dominant culture. They have the choice, and it's an easy choice to make. The term "complicit in white supremacy" also provokes an emotional response, but it would be pretty hard to argue that such rational-acting parents who love their children are not, at least a little bit, comfortable with using the reality of race in America to improve their own standing by placing themselves in proximity to whiteness!)