The reason neurotypical actors cannot play autistic roles is because they do things like "just never ever make eye contact" rather than "make eye contact but for too long/punctuate sentences with eye contact/look at a specific point behind the person's head"

Neurotypical actors play to a checklist. But those traits aren't always automatic or uncontrollable for us. They are often choices autistic people make to get by. Those behaviors have deeply personal history and context for us. They are artifacts.

Neurotypicals playing autistic roles is like buying a picture frame and displaying it with the stock photo it came with. You're supposed to have your own photos; your own history; your own reasons for your own behaviors. Stealing other people's is weird and glaringly obvious.

It's not just "don't make eye contact", because a real autistic person would have a history of being scolded for not making eye contact. So they will often have their own ways to try to do that. What ways? What compromises have they come up with? That depends on who they are.

And that's just the beginning. To build an autistic character, you do what we do: start with a sensory profile and neurological differences, and then build out the coping mechanisms that person would have come up with, slowly and organically, through each stage of their lives.

"Wearing headphones" is just the final behaviour - the one you see. But are they headphones for music, or earmuffs for silence? Is the person sensory seeking? Are they just avoiding conversation? Why? Whatever the reason, it needs to flow consistently into the rest of their life.