Now you're losing me. In what way does "culture" matter? Socioeconomic status has nothing to do with "culture".
That’s a cultural difference on display. Culture is not determined by race, so let’s not conflate the two. Culture is something you are immersed in and it does influence behavior.
There are also massive downsides to extreme cultural cohesion, looking at it another way.
But let’s not deny that social culture has a bearing on individual and group behavior. It has a massive impact. Conflating that observation with race or _racism_ seems a particularly unhelpful neuroticism of the US.