I fucked my share of black women in my time. It's pretty true that their BO can be hard to cope with once they sweat (compared to French caucasians which I know quite well). Difference is most of the time, black women know this and are extremely careful when it comes to hygiene. Even a pretty un-sophisticated black girl will have a bathroom full of products of all sorts. And they do their best to be as neat as possible. On the other side, I've smelled a good number of white vaginas that hadn't seen a bit of soap in more than a week I guess and made me hope I had a dead hyena rotting carcass with me going down there as a decoy.
if you are talking BO, are you talking about African chicks? Who do wash (And African men) but many tend not to use deodorant, antiperspirant yes.
As far as American---if you are dealing with trifling hood chicks, I could see that.
I remember in Jr High and HS, there was this Iranian/Middle Eastern girl who smelled terrible, and she caught hell for it---she would have gotten it from all but the pickiest Getbigger (of HS age, of course).
Her culture forbade the use of deordorant, and the person must have their "natural" scent.
She sometimes was brought to tears in class from guys making fun of her.