Those two tweets are absolutely it in a nutshell for young people with autism.
I've taught many children with asd now, including a couple who were very gender non conforming (and one who was referred to the Tavistock in the days where it seems to have been sane.)
The number of children who can only wear certain clothes due to sensory stuff or are desperate to wear the clothes they "can't" (the boys wearing or 'in to' anything remotely stereotypical for girls) is huge.
A large number have absolutely no interest in wearing or doing what their peers do.
It's much harder for the children who are more aware of themselves in comparison to peers, who are also the children who are likely to not be diagnosed till much later if at all, and struggle on in mainstream school. And so be around more peers who are exploring increasingly complex styles and identities and social communication nuances.
To me it's so very obvious, reading about and listening to Temple Grandin really helps understand this perspective as she talks about her clothes and interests and simply not having any interest in peer trends.
But to say any of that, is according to Joe Butler on the NAS website, transphobic.