Then let's talk religion instead of race, because you can control your religion actually much easier than you can control your socioeconomic class.
If someone publicly declared, say, Muslims or Jews to be ignorant and hateful because they knew six people of that group and it just so happened that those six were ignorant and hateful, what would you say? "Hmm, good observation, I like your methodology"?
I did not declare that I did a scientific study. However, if there was six families on my street, all the same religion, and all had great difficulty in parenting their children, I might wonder what it was about them that created that. But, what else do they have in common, and why are they poor parents? In the case of the six I know, they took a laissez-faire approach to parenting and all spent inordinate amounts of money on their kids in lieu of spending time with them. The religion of making money? The religion of greed?
Do I think that all wealthy people are bad parents? No. However, I do think that it is difficult to become wealthy without being selfish and unconcerned with the outcome of others. This propensity might make being a caring and giving parent that sets an example of community ethics difficult. This is what I have observed on my street, and in my career. Over the course of my professional life, 100% of my clients were wealthy people, and none were people I would want to spend any time with.
I think people at the extremes tend to be anti-social in some regard. Many of our poorest suffer from mental illness and other problems that make it difficult for them to function. I think this is true of many wealthy people as well, but their "problem" is manifested in such a manner that they can make money, therefore earning the admiration of many, but that does not mean they are healthy in how they function in their relationships with people.