If I have 3,400 to my name and my deductible is 2,000 (common from what I've seen). And my rent is 1,500 due next week, I'm not in good shape financially.
1. Insurance only pays some fraction of what can be very high bills, and providers notoriously send bill-like invoices trying to get you to pay for things which were paid in full by your insurance company. Many people will be pressured to pay things and uncomfortable standing up to a huge provider’s legal department.
2. Many employers have favored plans which increase deductibles, and the people with the worst plans are also paid the least and so will struggle to have enough cash in reserve for those larger payments.
3. Hospitals commonly have unrelated specialists show up for a couple minutes to add billable consultation hours. If one of those doctors isn’t covered by your plan, you get the bill even if the hospital itself is in network or you were, say, unconscious at the time or unaware that you could turn down their “help”.
4. Insurance is tied to employment: if you have a medical emergency which affects your ability to work, guess what happens to your coverage?
Most Americans have health insurance of some form.