For what it’s worth, my point of differentiation between ‘schizoid autism’ and neurodevelopmental autism is elaborated on in this book:
https://archive.org/details/in.ernet...de/1up?q=sulky
You can type the key word “autism” into the search-appendix of that book and see where it takes you. It’s very interesting and adds nuance to people the current neurodevelopmental framework-understanding of autism doesn’t apply to or box accurately. Under the other framewirk, autism’s more a symptom than a disorder.