Noticing that 13M number was in a forum dedicated to another topic, let's bring it back here.
Brookings Inst:
The tax legislation reported by the Senate Finance Committee last week included repeal of the individual mandate, which was created by the Affordable Care Act (ACA) and requires individuals to obtain health insurance coverage or pay a penalty. The Congressional Budget Office (CBO) has
estimated that this proposal would cause large reductions in insurance coverage, reaching 13 million people in the long run.
Supporters of repealing the individual mandate have argued that the resulting reductions in insurance coverage are not a cause for concern because they would be voluntary. Rigorous versions of this argument acknowledge that individuals who drop coverage would
lose protection against high medical costs, find it harder to access care, and likely experience
worse health outcomes, but assert that the very fact that these individuals would choose to drop insurance coverage shows that they will be better off on net. On that basis, advocates of repealing the mandate claim that its repeal would do no harm. However, this argument suffers from two serious flaws.
The first flaw in this argument is that it assumes individuals bear the full cost of their decisions about whether to obtain insurance coverage; in fact, one person’s decision to go without health insurance coverage shifts costs onto other people. Notably, CBO has estimated that the departure of healthy enrollees from the individual market spurred by repeal of the individual mandate will increase individual market premiums by 10 percent, causing some in that market to involuntarily lose coverage and causing those who remain to bear higher costs. In addition, many of those who become uninsured will end up needing health care but not be able to pay for it, imposing costs on other participants in the health care system. Because individuals who choose to become uninsured do not bear the full cost of that decision, they may choose to do so even in circumstances where the benefits of coverage—accounting for its effects on both the covered individual and the rest of society—exceed its costs.
The second flaw in this argument is that it assumes individual decisions about whether to purchase health insurance coverage reflect a fully informed, fully rational weighing of the cost and benefits. In fact, there is strong reason to believe that many individuals, particularly the healthier individuals most affected by the mandate, are likely to undervalue insurance coverage. This likely reflects a variety of well-documented psychological biases, including a tendency to place too much weight on upfront costs of obtaining coverage (including the “hassle costs” of enrolling) relative to the benefits insurance coverage would provide if the individual got sick and needed care at some point in the future. It is therefore likely that many people who would drop insurance coverage due to repeal of the individual mandate would end up worse off, even solely considering the costs and benefits to the individuals themselves.