No official diagnosis because that costs money in America, but almost certainly some variety of the AuDHD combo. So this is based largely on my own experience.

I think the main factor is subtext. Allistic people tend to know, or assume they know, the subtext intended in social interactions, including the consumption of media; frankly they just don't think about it that much. Autistic people have to analyze scenarios to try to logically deduce the intended subtext.

That means when autistic people consume media, they don't really have an assumption of subtext, or at least not a neutral one. As they analyze the scenario to try to deduce it, the obvious motivations reveal themselves. Obviously this ad is trying to convince me to purchase this good or service, obviously this highly biased ”news" is trying to push a narrative unsupported by the raw facts.

It's more difficult to propagandize people who scrutinize the propaganda. There is no subconscious assumption of neutrality, we know everyone is trying to push some agenda, subconsciously or otherwise, and in the process of masking we learn to try to figure out what that agenda is.

The same training we use to not seem like robots and make friends, also trains the ability to detect other unspoken intentions. We analyzin' err'ything out here.

It also probably doesn't hurt that a lot of the common mustering points in propaganda revolve around fitting in and conforming to (allegedly) implicit normal social norms. That seems to be an unusually poor motivator among those on, and especially to one end of, the 'spectrum'.