It is possible though, to unify those things, and to see those other effects also as second or third order effects of the same underlying deficiencies that cause problems in social interaction. I believe, for instance, that our super power as neurotypicals is our ability to see, process, model and make sense, especially in real-time, of what's inside the minds of other people. In a way, we are wired to be comfortable with multiple worlds or perspectives around us, because we can see them, process them, and make sense of them. It makes sense to me that a person who is less good at this, will end up seeking a model of the world that is more rigid. If the worlds of other people around you seem chaotic to you, and uncomprehensible, then you will seek an environment and an understanding of the world that is more static, rigid or fixed. So, I think, at least on a conceptual level, it's possible to link the root causes of social problems to the root causes of the need for rigidity and stability.
That's a fair point.
Excellently put.
But the effects of autism are visible outside of social interaction too, with repetitive behaviors, intense focused interests, trouble with adapting to change, rigidity in lifestyle, etc.