"Only crazy people say things they can't explain."
What do you mean by that?
Okay, just kidding.
I don't think the term "white culture" actually means anything specific, beyond "non-ethnic culture." There is no specific "white music," as you might include anything from Beethoven to the B-52s. There is no specific "white cuisine," as in some places it means the same as "soul food," including catfish, pig's feet, poke salad, collard greens, and other things one wouldn't eat if one could get anything else, but in other places it might mean Irish corned beef and cabbage, English Shepherd's Pie, French fried 'taters, or German schnitzels.
It could be referring to scholars, such as W.E.B. Dubois or Frederick Douglas. Oops, they're Black.
Or it could be science, such as the inventors of the disposable syringe, the spark plug, or the man who made the discovery that the peanut actually had nutritional value. Ooops, they're all Black.
I don't know. It probably isn't more than a protest against the concept that "Black America" is different from "America," rather than completely inseparable from it.