Blacks are by far the worst in terms of genetics. Hispanics are pretty similar to whites & asians, they just come from worse, more backward cultures in Central/South America. Whites also do badly in bad cultures, if you look at the former Soviet states.

But blacks? Unsalvageable. Just look at what an utter and total shitshow Sub-Saharan Africa is, and even when you take the blacks out of there and put them in rich white countries, they still end up way below everyone else in IQ and other outcomes. If you put in huge effort, you could probably close that gap somewhat, but they'd always act as a drag on everyone else.