Only for those on the lighter edge of the spectrum. I have a severely autistic sister who requires constant care and could never be functional in society. I feel I have more right to speak for her than the OP does. The neurotypical or neuroatypical decision makers argument doesn't really play when the individuals we're discussing lack the ability to make decisions in their own best interests.
But your sister, and her family, needs better accommodations from society.
She needs better treatment, so perhaps someday she could live something even resembling a normal life. She already gets plenty of accomodations from the government and society as a whole, living in a group home, etc. I don't know what other accomodations could really be made.
Yes, just as, as a man who's of below average height, I also can speak for little people.