Ponzi schemes actually already have a clear definition, and what you're describing isn't actually a Ponzi scheme

Travel insurance is especially terrible, because a lot of the time it's a pretty substantial premium, and actually filing a claim on it is a HUGE PITA.

I worked for a traveler insurance company before, and we denied most claims that came in. People would buy insurance on a $100 concert ticket, paying a $10 premium for the insurance, then when they'd go to file the claim, we'd require a doctors note, so now they also have to cough up a $20 copay and a whole afternoon just to get a note saying "yup, this person is sick". And that's just one of the many ways people got fleeced. During COVID, a lot of travel insurance claims got denied because illnesses resulting from pandemics aren't covered in some policies as well

nothing conspiracy theorist about it at all. If anyone gives you sideways looks when you mention that insurance is a scam, just point out the very simple and undeniable fact that insurance companies are (very) profitable. That means, by definition that the average customer pays more in premiums than they get in payouts, and not just a bit more, a lot more, as that profit they make is after they pay their thousands of employees, award multi-million dollar bonuses to their executives, pay for their bigass skyscrapers, and all that other shit. If insurance was a "fair" deal, they'd be losing money from the administration costs

Always self-insure if you can afford it

Why would you not get that? That seems like such a stupid risk not to get that.

Pretty much for all the reasons I said in my comment - you'll almost certainly spend more on premiums for travel insurance than you'll ever claim (this is true of all insurance) and the expenses incurred by self-insuring are generally manageable. Even in the two situations you refer to, we're "only" talking about costs of a few thousand, and both of those are highly unlikely events that most people go their whole lives not dealing with. you're much better off putting the money you'd spend on that travel insurance into an emergency fund to cover those kinds of unexpected expenses.

Insurance is only a good financial call if you risk completely bankrupting yourself by not having insurance, otherwise you're just trading potential lump sum costs for small continuous costs, and the premiums will generally always wind up being more than what you're saving (because if they weren't, then the Insurance companies wouldn't be making so much money).

That being said, it's your money, if you'd rather accept that you're paying more over a lifetime on travel insurance than you're saving just to have the peace of mind that you won't have to dip into savings for any incident that happens before or during the trip (assuming your incident doesn't fall under one of the many carefully crafted exclusions that the insurance companies add to their policies to prevent paying out, which it probably will), then by all means, buy it - but if you're buying it because you think it's the financially savy move, and you have at least a few grand in your bank account for emergencies, then you're kidding yourself.

I got travel insurance recently for a hiking trip with my wife. We had an emergency and my wife had to be airlifted out by helicopter, and we were so glad to have the travel insurance because it covers emergency evacuation up to $10,000 (and the helicopter costed around $5,000). Awesome, right?

Well... actually no. Turns out, the terms of our policy dictate we needed to call insurance first and have them organize the airlift. Since we dialed 911 and organized the helicopter ourselves, our insurance won't cover it. I guess it's my fault for not reading the fine print, but it feels pretty scummy from the insurance company. Even if we had read the fine print, in the moment I don't think I would have remembered as my immediate instinct is to contact emergency services.