Since others are picking apart your argument in the large, I'll just add this. Institutional racism, though it continues to manifest in the present, can only be fully understood through history: the extremely racist practices and policies of past generations of Americans have had compounding effects through time on the populations subjected to them. Regarding Asian American immigrants, the vast majority of them have only arrived since the 1960s[0], so they've had much less time to be dragged down by systemic racism. And additionally, the fact that they are lighter of skin tone tends to make them a less targeted group by racist actors.
>Or why we see common patterns of achievement and behavior between races across societies with wildly different institutional histories?
Who is 'we' and what exactly do 'we see'??? I'm dying to know.
[0]http://www.migrationpolicy.org/article/asian-immigrants-unit...