Interesting perspective. It’s also an outside looking in one, which is typically how autism and ADHD has been diagnosed in the past.

I believe a large portion of the people around me are ND, and there is a general resistance with acknowledging this because of stigma and the majority of diagnoses in the past being the more obvious ones.

My daughter could be compared to your brother in the autistic behaviours she has now and pre-diagnosis, but it was the onset of these behaviours that led to her getting diagnosed rather than the diagnosis triggering the behaviours. It’s autistic burnout. Had she have had support before hand, eg OT, things may not have escalated this far.

So my short answer is that it’s autism/ND acceptance that needs to change, not the rate of diagnosis