Note: This is primarily a shower thought post. It relies on information I had prior to taking my shower this morning.
Let me get this out of the way: Aspec does not mean autism.
This makes a lot of cultural sense, especially when you consider how people enter the communities, and the commonly known portion of their histories.
For those on The Spectrum, like myself, there are two ways to enter the community: Community first or Diagnosis first. If you were diagnosed when you were younger, you generally have a label and a label set you adopt before you have a community. This includes informal shorthand like “Aspie” - when I want to informally say that someone else is like me, I’d probably say something like “I think x is an aspie”. If I wanted to informally group people like me together to say we experience something, I’d say “aspies experience x”.
So essentially we are coming into the larger community with our own labels and informal terms. And while we could change them to be more inclusive, people on the spectrum tend to be resistant to change, especially when you are changing something that we have relied on for comfort for who knows how many years, and as an explanation when having to deal with others. Changing our labels just because there’s a larger community is uncomfortable at best.
Adopting formal language, and using it to refer to a larger group than before, however, is significantly more up our alley. When I say The Spectrum, I am not just talking about aspergers, but autism as well. It’s a way of adopting a group identity without giving up my personal label.
Those who entered the community through the community and gained a label afterwards would likely choose the labels they think best reflect them and move forward from there.
The build of the term itself also reflects our tendency to want to be more precise with our language. The term is completely written out or said any time it is started, which is why you see “autistic” instead of a, and “Spectrum” instead of “Spec” - we are talking about our specific spectrum. The shortening to “The Spectrum” just reduces it’s size to something that can change it’s part of speech more cleanly, but I doubt it would be able to shrink more due to loosing precision (Autism is always implied when The Spectrum is on it’s own).
Asexuals, on the other hand, have a completely different culture and history. Asexuality as a label actually came from a group that was using bisexuality as a label, meaning asexuals were talking to each other and trying to figure things out without having a term to themselves. Even as its own label, it continues to have discussion about micro labels. In this sense, asexual is both a micro and a macro label. A-spec people also use the macro label to handle discussions with those outside the community, sometimes to avoid having to explain their micro-label to those who may not be receptive. Additionally, there are aromantics who share a number of the experiences and are in need of a label.
These factors; people having the label asexual before they have their specific label, people needing to use the macro label as their primary label, and aromantics needing a place in the community, having an inclusive informal shorthand label makes sense. “aspec” or “a-spec” also plays the role of “gay” or “bi” in that it is ambiguous as to whether it’s romantic or sexual attraction involved, being another plus.