Comment by cma

I think he's just trying to choose a point in time when mental healthcare was more primitive to go along with saying the diagnosis is more sophisticated now.

A main thing is that people with autism would just be classified as generally mentally disabled and the rise in autism is highly tied a drop in that general diagnosis. I don't think that covers 100% of the rise but does seem to make up the big majority.

U.S. special-education autism classification was created in 1994 and tied to a big rise in diagnosis.

https://news.wisc.edu/data-provides-misleading-picture-of-au...