Yes all people are weird, and autistic people are people, so it's no surprise they are weird. I don't think this is a failing of Western imagination, I'm not sure who gave you this impression.
Autism isn't about being weird or quirky though -- it's a developmental disorder and the behaviors associated with it are disabling in our society. This is characterize as having "significant impact" on ability to function.
Well, no. Many of the behaviors associated with it, even the literal diagnostic criteria, are extremely beneficial in our society. It's not just a weird coincidence that many of the most successful tech, engineering and even business figures could be (and in multiple cases have been) diagnosed with autism of varying degrees, notably post-facto.
If anything I think the rampant over-diagnoses of middling cases is itself extremely harmful. Because it's going to lead otherwise perfectly viable humans to think that things are just out of their control because they have whatever the trending diagnoses in psychology is, and a diagnoses of failure becomes a self fulfilling prophecy. Suicide rates among those diagnosed with ASD, while having at least average intelligence, are ridiculously high. [2] Whatever is happening with these diagnoses is not this self affirmation bs people are spewing.
A bit more than a hundred years ago we'd have been having this topic, with the context of phrenology [1]. A nice little quote from that page: "Phrenology has been psychology's great faux pas. — J.C. Flugel (1933)." And so too will autism be. Until soon enough we might start to accept that psychology is not just a pseudo-science, but an exceptionally destructive one at that.
Autism isn't about being weird or quirky though -- it's a developmental disorder and the behaviors associated with it are disabling in our society. This is characterize as having "significant impact" on ability to function.