> It’s that it actually is very difficult to prove genetic heritability vs effects in the womb because you can’t do twin studies, going back to my original comment.

You seem weirdly fixated on this point, and to your rhetorical disadvantage.

It is difficult to tell whether you are being accidentally or willfully ignorant. Maternal effects are well-accounted for in research. It is extremely improbable that we’ll ever find out that they have anything but a very minor influence on ASD compared to genetic factors.