The primary fault with the Affordable Care Act from a cost effectiveness standpoint (aside from not being a true single payer system) is that States were allowed to opt out of the Medicaid expansion. This leaves the rest of the country and the Federal government covering the healthcare costs of the uninsured populations of those States and dilutes the shared risk that would reduce costs for purchased plans. And it's no secret that the States who opted out score the lowest on healthcare outcomes and are invariably "red."