He was just a psychiatrist tasked with trying to figure out why all of these kids of rich parents were throwing tantrums at school and failing it, even though they had a normal level of intelligence, which in turn led to a pattern of behaviour that he found remarkably close to what Bleuler called "autism" in Schizophrenia, amongst them all.
He did say that people with AS were equally imbeciles as they were focused.... I don't think he'd see himself as an imbecile, personally, and he wasn't all that focused (his paper isn't written like a factual piece, rather like a piece of literature).