Jeremy Stangroom

I think it's pretty close to a general rule among American autistic advocates who have claimed the label for themselves without diagnosis, assessment, etc

That has certainly not been my experience.

Many of the people who claim the label for themselves without a formal diagnosis come to the realisation they're autistic themselves after a family member receives one.

Others come to see themselves as autistic because they know autistic people from other contexts, and realise how much they have in common. Sometimes those autistic people are very decidedly disabled; sometimes less so. Either way, most understand highly disabled autistics exist.

Right, but how many have spent a lot of time with autistic people with severe disabilities? And if they did, do you think that would change how they viewed the issues?

Probably a minority have spent a lot of time with such people. It's a substantial minority though; and many autistic advocates have high support needs themselves though, which is not obvious when you're meeting them through the internet. Of course it changes how you view things.

Have you ever been responsible for looking after the personal hygiene of somebody who screams & fights every time you come near? (I'm asking out of interest, not in an aggressive manner.)

I have been in more-or-less that situation, yes, although not someone who 'screams & fights every time you come near' - that's an oddly specific requirement! I have certainly been responsible for looking after people who have physically attacked me and made horrible noises at me.