Sabik made a comment that jelled a few ideas I've had into the light and ephemeral consistency of a conspiracy theory. I present this here not as a serious proposal, but more a kind of intellectual fairyfloss.

The defining characteristic of humans is their capacity for madness. Mammals have this to an extent (otherwise we wouldn't keep pets), but humans are the masters of it. One half of making this work is that we can create elaborate mental models of each other. That gives us a reason to be mad. But what of the ability itself?

In a way, going mad is the easiest thing in the world. It's a rationality consistent from moment to moment that is hard. However it still remains, what is the exact mechanism that humans use?

To introduce the other thread into the mix, a neurotypical human uses robust statistics to understand the world. A few unaccountable outliers to their understanding of the world will not cause them to give up on it. My theory is that what sets autistic people apart is that they use more conventional statistics, and are incapable of ignoring outliers.

There always will be unexplained and exceptional things, but might this tendency be hypertrophied in neurotypical humans compared to other animals, not simply as a way to robustly understand the world, but as a way to maintain a useful madness (demanded by the collective) in the presence of facts that contradict it? A way to swallow the Big Lie without choking.

Here's the cherry on top: Consistent with the above theory, noted bovine psychologist and author Temple Grandin claims that her autism is what gives her special insight into the minds of animals, because her mind works in a similar way.