This puts medical boards in a sticky situation where they have to be inclusive since there's not enough research to say the latter group are definitely not autistic.
I'm in the camp that you shouldn't diagnose an issue without clear physiological or chemistry differences, but I'm not in control of the medical boards. I think we all agree that you shouldn't self-diagnose.
Most people who use terms like autistic, bi-polar, sociopath, narcist, etc. are using the terms incorrectly.
Also, I suspect you are correct that most ASD diagnoses do not use brain scans and rely on a trained professional's judgement and observations. That fact does not mean that autism does not exist or that some autistic people may have physical differences from neurotypical people.
Self diagnosis is often the first step towards a professional diagnosis.
You can choose to believe self diagnosis is low or zero value, but that's your own value judgement, which is separate from "can" and "cannot".
What makes such a diagnosis incorrect when various forms of social awkwardness satisfy criteria A and D of the diagnostic criteria [1], and all of the criteria for social pragmatic disorder[2]? In the DSM-V-TR era psychiatrists are instructed to not just judge somebody to not be autistic if they do not appear socially awkward, and to additionally ask if they find social interactions distressing, and observe them for longer in more naturalistic settings to find the deficit in social functioning[3] as part of a thus far continuously lowering diagnostic bar as to what is considered sufficient social awkwardness to be diagnosable.
>Autism has clear physiological differences in the brain.
Which physiological changes in the brain make you autistic, or put another way, which physiological changes in the brain must you lack to NOT be autistic? I've heard of any autism diagnosis's and self-diagnosis's and I've never heard of any of them being based on a brain scan and yet people go around calling others and themselves autistic. I've never heard of a diagnosis being lost or gained due to a brain scan.
I've heard this insistence that we can infer the territory, the neurological conditions of peoples brains, from the map, the behaviourist diagnosis, and there may be a correlation but it can't be said that any given person with an autism diagnosis has any given specific neurological change. The only thing we test for IS behaviour, and infer biology from it.
[1] https://www.cdc.gov/ncbddd/autism/hcp-dsm.html [2] https://en.wikipedia.org/wiki/Social_(pragmatic)_communicati... [3] https://www.reddit.com/r/aspergirls/comments/th9hku/dsm5tr_n...