my theory is they overlap because one might have triggered the other. struggling kid gets trauma for not fitting or forcefully molded to fit or even for trying but never quite reaching the "goal"

Agreed

A lot of people on the spectrum have complex trauma just by existing in a world for neurotypicals who "other" us from a young age, add to that any familial abuse for not behaving well enough and it's cPTSD for most of us. A lot of AFAB people on the spectrum also end up in abusive relationships and friendships as well. I don't know for sure that that isn't a universal thing that affects the entire gender spectrum or not.