The way I see it, Autism is more a kin to color-blindness, while crippling anxiety is na actual illness/disorder that should be addressed with therapy.

And while someone on the autism spectrum is born that way, anxiety is inflicted. Of course, Genetic temperament plays a role in one's predisposition to anxiety, just like with many physiological illnesses.

In a nutshell, Autism is neither an illness or disorder, but merely a "different order", while crippling anxiety is actually a disorder.