I think insurance policies cap maximum out of pocket costs. I'm on a cheap policy ($300/month) that caps annual out of pocket costs at $12K. I have that $12K on standby if something really bad happens but it's been years and no issues yet.

Do not embark on such a project if you have some chronic conditions. Start in a good shape. Generally keep a healthy lifestyle: no heavy drinking, no junk food dinners, enough motion, etc. Stay away from high-risk pastimes like snowboarding, motorcycle racing, etc. Wash your hands and do other trivial things to keep infections reasonably away, especially when far from thickets of civilization.

Things like that. Do what you can not to get badly sick or injured, because medical bills can quickly burn through your savings.

No doubt, but beyond the practical advice you've offered, a lot of health in the long term comes down to luck. Some people eat perfectly and still develop cancer at age 34, others never develop it despite "living a hard life".

On average, health insurance doesn't seem optional.

:-/