It’s not inability to assimilate that’s not needed, it’s unwillingness. We don’t need a Balkanized America, but we also don’t expect everyone will be exactly the same. Diversity for the sake of diversity is dangerous.
The biggest problem with this “article” (atrocity) is that he claims it’s study after study that knock down the truth, when he is cherry picking his sources from the most dramatically left-wing anti-American bought and paid for studies ever.