[olliej]

private health insurance in the US is (even under Obamacare) expensive, and the deductibles are high if you're on those cheap plans.

Under an Obamacare cheapest possible insurance option you're not going to be bankrupted by (for example) a heart attack, but you'll still be paying the bill for a long time. That ignores hospitals like SF general that charge you directly (and are out of network) so you can still be trivially bankrupted.