>This to me says that assimilation doesn't work

Even the whole argument about success rates of assimilation aside, this doesn't seem to check out.

How does this whole "assimilation doesn't work" argument even flow from the statement? Asian Americans referenced were all born in the US, grew up here, went through the education system here, etc. There is nowhere they need to assimilate to, they were born Americans and grew up here. This is their primary culture, not that of a country where their ancestors were born.

I am leaving a big possibility that I completely misunderstood your comment, so please correct me if my interpretation of it was incorrect.