I suspect it’s equally, if not more, related to culture. Asian culture reinforces academic achievement, Black culture not so much. However, Thomas Sowell found big differences related to achievement among African blacks as opposed to West Indian blacks; again suggesting that culture is the key.
I’m a little tired of the use of the demographic “Asian”. It has no meaning except in the mind of people who don’t think too deeply. Do the Japanese have any ethic, cultural, or religious ties to Pakistanis? How about Sri Lankans and Mongolians? What about Koreans and Israelis? Russians and Filipinos? They’re all “Asian” but may not be perceived or reported that way. The point is that data presented the way it is currently being done is useless and misleading at best, and needs to be broken down into some meaningful measure.