My parents are from Taiwan, I was born in the U.S. I have reflected on this topic, and my thought was that South Asians, due to British colonization, appear to adapt more easily to American culture. Comparing immigrant parents from South and East Asia, (anecdotally) I have noted that South Asian parents speak English with greater facility than East Asian parents, which I have attributed to the effects of the British Raj.
I also have noted that South Asians have a strong culture that resists rote Westernization, which I attribute to native Indians (etc.) learning over time about what to sustain and what to adopt from the culture of their British overlords. So I conclude that when South Asians emigrate to America, they have a "leg up" in adopting to American culture, while East Asians experience culture shock to a much greater degree. Not only is the language more unfamiliar, but East Asians don't have the historical/cultural experience of keeping their culture separate from a Western culture as South Asians do. As an example, look at the relative interest of children of immigrants in the USA's National Spelling Bee.
I therefore think that because of these reasons, and because I think East Asian immigrants are as bright as South Asian immigrants, that we will observe a bolus of super-successful East Asian immigrants one generation later than when we observe a bolus of super-successful South Asian immigrants.
Now obviously these observation are generalizations, but I suspect that the "strong accent" observation of PG is not just a proxy for facility with English but a measure of cultural adaptation than may be helpful in becoming successful in the USA.
I also have noted that South Asians have a strong culture that resists rote Westernization, which I attribute to native Indians (etc.) learning over time about what to sustain and what to adopt from the culture of their British overlords. So I conclude that when South Asians emigrate to America, they have a "leg up" in adopting to American culture, while East Asians experience culture shock to a much greater degree. Not only is the language more unfamiliar, but East Asians don't have the historical/cultural experience of keeping their culture separate from a Western culture as South Asians do. As an example, look at the relative interest of children of immigrants in the USA's National Spelling Bee.
I therefore think that because of these reasons, and because I think East Asian immigrants are as bright as South Asian immigrants, that we will observe a bolus of super-successful East Asian immigrants one generation later than when we observe a bolus of super-successful South Asian immigrants.
Now obviously these observation are generalizations, but I suspect that the "strong accent" observation of PG is not just a proxy for facility with English but a measure of cultural adaptation than may be helpful in becoming successful in the USA.