That’s not what GP is saying. He’s saying that a term like “autism” is a lasso trying to capture a gigantic number of individual traits and symptoms. This is true of any other “psychiatric disorder” as well. There is no “autism”, there is no “ADHD”, there is no “OCD”, any more than there are tables or chairs.

Something being a table is a label we slap on it to abstract certain attributes, that allows us to reason about it without having to think about all of the non-table-attributes it has. What do tables do? What can we do with them? We can put things on, eat off them. We can’t feed them to our pets. We can’t use them as a trampoline. The object being “a table” is just a categorization we make to allow us to think about the object; it isn’t something that the object is.

Similarly, people aren’t “autistic”. They’re just people, who have certain traits, which psychiatrists have decided should be lumped into a category called “autism”, because they’ve noticed a cluster of other people who have similar traits. So, from this standpoint, someone “being autistic” does not tell us anything. We can already see that person’s traits or characteristics. That categorization might be helpful to some people, and it might be harmful to other people; and they should use or avoid using it accordingly. But they can choose to do that, because “autism” isn’t a “thing” - it’s a mental construct.