If you have a minority that has every disadvantage but believes that they CAN succeed by their own effort, that minority will succeed and it will reduce bigotry against them. Indeed the history of the USA supports this - we have had wave after wave of disadvantaged immigrants. They have nothing, have trouble with the language, and are widely discriminated against. But a generation or two later you have seen Italians, Koreans, Chinese, Vietnamese, Russian Jews, Afghans, and many other minorities integrate into the mainstream and do well.
But get a victim culture established in a minority, and things won't improve for them. They are unlikely to actually face more discrimination than, say, Cambodians did when they arrived here penniless and not speaking the language about 40 years ago. But they will have a worse future.
Look at it a different way. If you're from a disadvantaged minority, you've likely got a strike against you for having a bad background, and another for current discrimination. Add a victim mentality, and you're out. It doesn't matter how good the evidence is that you're an actual victim, it is the mentality that you can't afford.