It's not at all comparable to Social Security. One is an actual social safety net designed to have the government provide at least a small amount of safety net.

The ACA, Romneycare and the heritage plan are all about not providing any safety for the citizens but ensuring the health insurance industry is taken care of at the expense of the citizens. This is simply because they can't handle the thought of actually supporting citizens with an actual Healthcare System people can afford.

Hell the Heritage Foundation was proud of Romneycare and only attacked the ACA as it was a win for dems as it was their plan and couldn't admit the dems did it because of how racist they are.

The idea of pooling the purchasing power of individuals

Except the ACA fails to accomplish anything close to that. It's not designed for it simply requiring minimum levels of coverage. It isn't even an option in most states. As others have stated it doesn't matter if a person is insured if getting treatment still bankrupts them.