Very simple fact:
So often autism is treated as a childhood disorder. It is neither a condition unique to children, nor a disorder.
There are many more autistic adults than there are autistic children. For every autistic child, there are at least three autistic adults. As the general population ages so too will the autistic population.
I make a distinction between disorder and disability. And a great many of the disabilities attributed to autism are in reality, social constructions created by non-autistics that are punitive when we are our true selves. Don’t forget that American psychiatrists didn’t remove all references to homosexuality as a disorder until 1987. In time, autism too will no longer be considered a disorder.