Obviously I agree with you on this, but after years of having to confront smart people on HN who disagree with me fundamentally on issues like this, I'm trying to keep a more open mind.
The moment someone can supply an objective, verifiable, scientifically valid proof that formal discrimination would have ended on its own, then I'll consider it. Otherwise, it sounds like after-the-fact rationalizing from people who were part of the problem and ashamed of themselves (as they should be). Ideology and academic hand-waving about the principles of some Invisible Hand moving society forward simply did nothing. The hands that broke the shackles were very visible, covered in dirt sweat and blood, and very pragmatic.
In general, I steer clear of ideological decisions with hand-wave philosophies which hold their conclusions to be self-evident. I see a lot of this in economic discussions, too. My challenge is for these ridiculous vapid ideologies to come with formal justification that doesn't involve circular reasoning or false premises.
But then you look at the last 20 years and you wonder whether quickly changing legislative reality is a good thing to want.
How could you do this for any counter-factual of a government policy? Is criticism of the PATRIOT Act stupid if someone cannot provide an objective, verifiable, scientifically valid proof that we wouldn't have been attacked without it?
So, no, criticisms of the Patriot Act backed by data are not stupid, especially if the criticism is up front and says "we believe this to be true."