Why exactly is dark matter unintuitive to the layperson? (Any more so than say, germ theory, or praying to an interventionist god)?
For me it's because the explanations don't actually make sense. The classic example to me is the galactic rotation "problem". It gets resolved by suggesting a spherical cloud of dark matter surrounding a galaxy. Great, but why would it affect the galaxy normally but take on such a distribution? The solution raises more questions than the problem. Not to mention it's a whole new kind of matter we can't detect. It's almost magical thinking.
Electromagnetic interactions radiate off energy but not angular momentum, so a spinning sphere of gas will flatten over time. Dark matter doesn't interact electromagnetically and thus sheds energy much more slowly.
That’s all it is I think. Sabine (and probably others) have done a great job of explaining these concepts for the layman audience.
This article, and so many like it, don’t do that. So the physicist is left shaking their head, and the layman comes away still thinking “what a giant kludge that dark matter is”.
In realm of everyday experience neutrinos and proposed dark matter would be the same ghostly thing.
No, but as a posteriori reasons go "everything else couples to the weak force" is a pretty good one.
> them dark matter is unfalsifiable
Only insofar as all the ontological content of a physical theory are unfalsifiable: you can always shift complexity around between state and dynamics if you're willing to pay the price in elegance. Consider Kaluza-Klein theory, for instance. In some sense this demonstrates that classical electromagnetism is unfalsifiable - but no one actually cares.