I find that in a lot of conversations about racism with white people, the problem of recognizing their racism comes down to a misunderstanding of terms — especially as the language has evolved so much. The older community is working with terminology that the younger ones have coopted to have different meanings.
When you start by saying racist to older people, their working definition is a KKK member or someone who actively works to harm people of another race. It is not something you can do passively. You did a good job of clarifying, but it is so rarely done.
I think you overstated the number of white people who fit your racist description. I’m white and honestly don’t know anyone personally who fits that description. I grew up in a majority-black community of New York, but we heard there are some on Staten Island. Regardless, it exists and its a problem. And it will stay a problem because of the whole idea about what race is.
By the way, the racism you describe is not limited to white people. It is just as pervasive in all groups, but because whites are the majority and have some bad historical baggage to deal with, it is the most conspicuous and numerically the most harmful.