If you're asking if autism is more prevalent than we used to think, which is the less inflammatory question you should be asking, then yes I think the rate of diagnosis should be higher. I am undoubtedly autistic, but was not diagnosed as a child and the current 5 year NHS waiting list is a barrier to me accessing a diagnosis now (Wales, no Right to Choose here).
My daughter has a diagnosis, her older brother is on a 3 year waiting list despite me approaching school 4 times with concerns about him during his time at primary. He's now going through GCSEs awaiting the diagnosis that could give him extra support.
But to go back to your question, I don't understand how you think a greater diagnosis rate would get us out of making the world easier for people with diverse characteristics to live in? Surely the opposite? I would love it if the world was more accessible for me and my children. You say you have a child awaiting diagnosis - you must have some ideas of these barriers?
We can't attend birthday parties - even with loops or ear defenders they're too noisy. We can't go swimming - of the 6 council run swimming pools in our area, none of them offer quiet sessions. We had one special quiet session in the summer holidays which was the first time we'd been swimming in a year. It's my most hated month of the year, October brings massive change to our outside environment and fear around every corner, no safe supermarket visits even.
Everywhere is too loud, too flashy, too busy, queues, people, smells, things to look at, ambulances, fears. The things I have to predict and mitigate for everywhere I go, people looking and staring at the screaming, judging me for my shitty parenting.
And my children are what you would class as the ones who you would deem high-functioning, borderline undiagnosable. If you meet them with their masks on, they're not autistic, just 'normal human behaviour'. We're all great at it. I have a lifetime's experience of pretending to be a human.
It's fucking exhausting and I am utterly broken by it. Your attitude is so disappointing if you truly are a professional.