I'm Asian too. I don't think it's because of raw intelligence. Asians work hard, but in a very confined way, and visible way. For example in high school, you work hard in school to get into a great college, your hard work is visible.

Scientific discovery and technological innovation takes more than hard work, it takes the willingness to be obsessed with specific and sometimes obscure fields and forfeit social prestige and stability. Neither of those things are praised by the Asian culture.

That might be due to culture.