That is how health insurance works in New Zealand.
If you want private health insurance for say $50 a month[1], then insurance gives access to procedures more quickly and the rooms are much nicer than the public health care system. It may give access to rare but expensive procedures.
If you don’t want insurance, then the default is the public healthcare system, which is paid for by taxes. You will usually be in a ward with other patients. You pay small amounts on use (to prevent abuse, and even those amounts are reduced to nearly free if you are poor). The level of care is reasonable, but can be slow for non-urgent elective surgery, and extremely expensive procedures are not available. The public healthcare system handles ongoing chronic conditions much better than a private system could.
[1] You can see a quote from https://www.southerncross.co.nz/ if you give your age, gender and tick whether you smoke. Note that Southern Cross is a nonprofit co-op, most premiums get returned to members (on average, less an approx 10% administrative overhead).
Germany allows people to opt out entirely, although there are a bunch of conditions and limitations. Most people don't, so the public system can still pay for itself.
Sadly in germany it's rather difficult to switch between public and private or no insurance. Or rather, it's very difficult to get back on a public insurance once you're private or self-insured. The best you can hope for is pulling it off once, maybe twice.
If you're avoiding paying into a system because you don't want to claim from it then letting you hop back on whenever you need it would destroy the system very quickly.
It's not that easy, luckily, if you're self-insured and have to take the service of a doctor, you can't switch just like that. It takes about a year of paper exchange with everyone involved to switch cleanly. Even then, any costs you started paying for from before will still have to be paid unless you're below a certain income bracket (or declare bankruptcy).
So if you were self-insured and broke a leg, then decided to switch back to insurance, you'd still be on the hook for the costs of the ongoing physiotherapy until it is healed back up. The insurance doesn't have to actually pay anything that happened before a switch (switching from public to public insurance or private to private doesn't have this limit, private to public and the other way round but you don't pay, your old insurance pays).
It's possibly one intention, though there are already laws that prevent you from going back to public insurance if you're over 55 years old as well as if you're over a certain income limit.
The only universal way to switch is to marry someone in public insurance.
I do not know the New Zealand system, but I suspect the base level of care is still covered by public funding and the insurance is only covering optional extras (like private rooms).
All NZers get treated for cancer or pre-existing conditions, within the funding limits of the health system.
Severe health problems don’t bankrupt NZers, and you are not locked into a job just to (a) keep your insurance, or (b) keep your insurance benefits.
How many recently unemployed in the US have lost cover for their pre-existing conditions?
I expect you can find the benefits list document for Southern Cross, if you wished to check out the details of cover for cancer or pre-existing conditions.
Cancer is not an elective surgery and gets treated with urgency. Across the Tasman Sea with a very similar system my father had bowel cancer removed the day after diagnosis in the public system and spent most of the recovery in no state to miss a private room.
Please look around you a little more. My buddy separated his shoulder snowboarding in Tahoe. He had a full time (40 hours a week) job at the time, but it didn't provide healthcare.
He couldn't afford to go to hospital, so never did. I was visiting from Australia at the time and was utterly horrified, having no idea the US worked like that. Now years later his shoulder is still screwed.
Of course people in the US avoid going if at all possible, it's horrendously expensive, and medical bills are the number one cause for bankruptcy in the US [1]
In a stack of OECD countries (all the other ones?) nobody has ever gone bankrupt from medical bills, because that's impossible.
There are people that cannot afford insulin. THAT is a problem. But the fact that he took a risk, for fun, and suffered the consequences, rather than having everyone paying for it? That sounds a bit reasonable...
Note: important that the risk is voluntary, optional and recreational rather than professional. Why would the collective bear the costs, in those circumstances? Why is that fair?
Person doesn't have insurance and injured themselves doing a risky activity, and can't afford treatment. If it's really bad, why not use bankruptcy, I can't imagine this person has anything valuable given the history you described.
What is insurance for? To cover risk of something bad happening. The bigger the pool paying for it, the less impact to any one person to cover all the risk.
Now imagine that was scaled up to a whole country. That's New Zealand. Check out the Accident Compensation Corporation. All medical costs related to accidents are automatically covered!
But who pays the costs! Everyone, via levies. How much? $2000 on a $150K IT income.
But how do you control costs? Who is entitled? Who is at fault? Surprise! It's a no-fault accident insurance system that covers all accidents.
In exchange for that, we gave up our right to sue in accidents for medical damages. Why pay a lawyer when they're not required?
I guarantee the average US worker that makes 150k (not an avg salary) pays more then 2k in SSI taxes that cover Medicaid. They pay all over again for private healthcare, probably in the 6k range if they don't have kids.
If you want private health insurance for say $50 a month[1], then insurance gives access to procedures more quickly and the rooms are much nicer than the public health care system. It may give access to rare but expensive procedures.
If you don’t want insurance, then the default is the public healthcare system, which is paid for by taxes. You will usually be in a ward with other patients. You pay small amounts on use (to prevent abuse, and even those amounts are reduced to nearly free if you are poor). The level of care is reasonable, but can be slow for non-urgent elective surgery, and extremely expensive procedures are not available. The public healthcare system handles ongoing chronic conditions much better than a private system could.
[1] You can see a quote from https://www.southerncross.co.nz/ if you give your age, gender and tick whether you smoke. Note that Southern Cross is a nonprofit co-op, most premiums get returned to members (on average, less an approx 10% administrative overhead).