You seem to think no one with autism is high-functioning.
I think you have completely misunderstood the post you are replying to. The author's whole point is that the syndrome formerly known as Asperger's is far less debilitating than those found at the other end of the autism spectrum.
There seems to be a contradiction in your positions here. You started by saying that Asperger's is/was "not really distinct from autism in any meaningful way", but now you are insisting that we make a distinction between high-functioning and the more severe incarnations of the disease. As the syndrome formerly known as Asperger's has been subsumed into the high-functioning end of the autism spectrum, you can't have it both ways.
Aspergers has no diagnostic or treatment criteria that distinguish from autism. The end.
For the limited purposes of the DSM, that may be true, but it is an invalid extrapolation to claim there is no meaningful distinction between the syndrome formerly known as Asperger's and what was meant by autism when Asperger's was in use. The fact that the former Asperger's is now regarded as a high-functioning autism spectrum variant does not justify this generalization, because the change is only in the language, not in what it denotes. The fact is that in many aspects of life, there is a huge difference in autism's impact across the spectrum.
I am also puzzled by how you can munge the definition of 'treatment criteria' in order to say that there is no difference between the treatment criteria for a nonverbal autistic person and someone with the former Asperger's syndrome.
My best guess is that what you meant to say is that there is no meaningful distinction between Asperger's and other high-function variants of autism.