I recently read Hillbilly Elegy, and one of the key insights I got from there was success seemed to be related to a stable home / family, and in particular a presence of mentors and role models.

I wouldn't be surprised if part of the success of Asians (South Asians + East Asians) also stems from the fact that divorce is looked down upon and extraordinary efforts are made to prevent it from happening. Divorcees are often social pariahs in these cultures.