Multiculturalism generally, but, for Whites, Desis in particular?
I previously updated my theory of autism to make it more general. That is, instead of being focused solely on the effects of South Asians on Whites (particularly northern groups like Finns), I considered that multiculturalism in general is the cause; diversity damages the amygdalas of young (mostly male) children of all races.
I still suspect that is true, but it doesn't necessarily invalidate the original thesis either. While, in general, overall diversity is the problem, we may ask specifically for Whites what is going on.
Looking at this picture, and remembering Bowery's original work in finding important associations correlated to autism rates. I believe it likely that South Asian phenotypes pose a particular risk for young (male) White children with respect to initiating the brain changes resulting in autism.
Those worried about autism need to reduce their exposure to diversity generally, and Whites, particularly those with young (male) children, should consider reducing their exposure to South Asians. Look again at the picture and try to imagine how a young White child would react to that.