Interesting thing about what Noam Chomsky had to say about the general popularity of single-payer healthcare: The public might favor it, but they keep on reelecting Republicans to Congress, and those Republicans vote against it. Even when they elect Democrats, often those are Blue Dogs who likewise vote against it.
When ACA passed Congress, it barely squeaked by because single-payer was removed. This was not Obama's preference but had to be done to get any bill at all. From a democratic point of view, we should have it right now because most people support it. But we do not have a popular democracy in which we get to vote on every issue.
The reality is that in many districts people will keep on voting against their own best interests because of the "dog whistle" issues some candidate brings up. Reality sucks some times.
