I'm not sure how to answer that, because I still don't believe what you're saying is correct. Living and teaching in Memphis for three years certainly gives one more perspective than
not doing so, but a school-district-sized parcel of Memphis likely doesn't even speak for Memphis as a whole, let alone all US cities.
I do expect that all low-income black people living in cities share some values, but that can be applied to any group. I wouldn't claim that low-income white people living in cities all have the same culture, either, despite the fact that they almost certainly share at least some of the same values.
Look, I'm not trying to say you're an evil racist. You just have biases (unconscious and conscious), just like all of us do. I just worry when people try to label a group of people so narrowly and homogeneously when there's more to it than that.