Jon Cohn makes an obvious point: the current dysfunctional and stratospherically inefficient US healthcare system impedes economic freedom. It does so because people stay in jobs they may not be suited for, because they fear losing health insurance. Small businesses are hobbled by the soaring premiums, and many individuals are discouraged from going out on their own, taking risks, creating jobs, because they would lose basic healthcare and be unable to afford it, or even fail to get it at all if they have a pre-existing condition. Since the financial burden is borne primarily by the private sector, US companies also have a massive disincentive to hire more workers, because of the soaring insurance costs of adding a single employee.
In my own case, I would definitely gain freedom with the ACA.
I'd have a chance to buy my own health insurance, even with a pre-existing condition, after comparing it with competitors in an exchange. That would free me to have greater flexibility to switch jobs, move, change my career, take a risk, and so on.
The ACA, in other words, is not just about security; it's about increasing freedom to live and work without the terror of being bankrupted or simply overwhelmed by the costs of individual insurance. That's why Hayek had no problem with forms of social insurance that guard against the hazards of human life – illness, accident, disability, etc. He knew that with random things like illness, it makes sense to have universal insurance against the inevitable physical travails of being human – so that we can be more free to experiment, innovate and risk.