I have referenced plenty of evidence in my post. Check the hyperlinks.

You go as far as calling them bull shit, in other words completely made up or 100% nurture. What roll does nature, our genetic heritage, play in personal traits or abilities/disabilities like these?

There is no evidence for genetic predisposition to explain such a massive trend in autism — nor there is for introversion/extroversion. They are based on subjective spectrums that seem to expand or retract depending on who examines them.

A very small percentage of the population has indeed severe learning disability and/or issues with socializing. Again, this percentage is extremely small. Thing is, with the "spectrum" theory, anyone can fall within that range and labeled as "autistic" with no other evidence other than a random person taking an interview and checking boxes.

If the parent is exposed to the idea of autism, even worse since their own bias will affect how those answers will be filled.