I think the term autism is mostly used as a substitute for a poorly raised or ‘trained’ child. It lets parents off the hook for a very poorly behaved, often bratty child.
As someone on the spectrum, I suspect you are right. It’s the hip new thing now. We were taught to cope or risk a beating at school. “Cope” is a curse word now. It’s considered ableist. Kids today get so invested in their “autism” that they burn themselves out.