you can combat racism and prejudice by improving culture

It's not that simple at all, poor people are stuck in a cycle of perpetual poverty, that's how Capitalism works. If you fuck up in life, and you can't afford to try again and get a high paying job, then you are basically screwed for a long ass time. It costs money to make money. If you live off welfare and can't get a job, there's nothing you can do but grow up stupid and bitter. Which in turn breeds another generation of people starting from poverty, you might say, muh bootstraps, but given the costs of college, housing, lack of jobs, it is enormously difficult to get a leg up in life IF you are born into poverty. So yes, black people could use a change of attitude BUT we have to put out our hand first to ensure that it's worth it. Otherwise, there's no reason not to be a bitter pessimist.

you will need to point to specific instances that affected blacks not just then, but today as well.

Capitalism. The blacks are literally the poorest of the poor, therefore they stay in a system of unequal opportunity. You don't think white people like to give up when they can't catch a break, either?

However, today just because a person is black or white does not generally correlate to them being poor or rich.

Yes, if you are born black, you are more likely to grow up dirt poor.

Even if it did, it would be an attack on freedoms to correct this (i.e. return stolen, illicit goods and money to blacks from generations ago).

No, a stimulation project is not an attack on freedom, we do it all the time. The New Deal wasn't an attack on freedom. Also, it doesn't have to only apply to whites, it should apply to people making under a certain amount of money or just poor people in general. This would still help blacks vastly.

Therefore, the country has set up a means of equal opportunity under the law.

Only in the most blind sense there is but realistically, if one student is raised by smart white collar workers and has everything in life planned and paid for, they have to struggle far less than someone growing up with a family income below 30k a year and with bitter stupid people. That's not my definition of equal opportunity, where if you're born poor, you tend to stay away. This applies to whites too.

The culture Shapiro talks about is what is holding them back.

Right so the terrible minimum wage, lack of jobs, ridiculous housing costs, ridiculous college costs, etc. Are you really telling me, that has nothing to do with holding back people in general?