I don't understand this rant. You acknowledge the spectrum has been expanded but then contradict yourself or display a serious lack of understanding by saying that a diagnosis implies being "overwhelemed by autistic traits". A level 1 diagnosis is defined as not being overwhelmed the way a level 3 would be.

I'm diagnosed as level 1 and I assure you it's something different than introversion. Not that it's necessarily a stronger thing. I didn't even get diagnosed until recently because my life has always been so functional that there was no reason for me to think I needed to be tested. The way I hear serious introverts talk sometimes, I'm glad that I have my traits and not theirs.

I have never been able to understand what it is about autism as a topic that drives people mad.

I have a similar opinion to the person you're replying to, and here's why: The spectrum is not particularly useful to anyone outside of the medical community. If you say "I have autism", that tells the other person very little. That could mean a vast array of things, it is so poorly descriptive of what that actually means for you that it's hardly even useful at all. I think the spectrum in and of itself isn't a problem, the problem is that there aren't more names for it. Clump common clusters of symptoms together and make a name for that specific clump, for example, and call it Foo Disorder, and now people can actually understand what that means. By expanding the umbrella so wide, it has made the disease confusing. If there were more specific things you could point to, it would be much easier to grok.