> only the old and the poor

Also government employees, and those under the care of the VA.

> Purchasing Power Parity, which also should be accounted for.

Yes, I agree.

To illustrate with a simplified example:

Imagine nation A has median wage of $20k and nation B has median wage of $40k. Also imagine that their income distribution is the same. Then, if healthcare costs in nation B are twice as high, healthcare is equally as affordable.

" So the average taxpayer has to buy their own health insurance in addition."

How the money is collected is pretty irrelevant (indirectly via taxes or directly by the insurance company or physician). What matters is the overall cost.

It is relevant due to the complexity and uncertainty imposed. When I lived in the US, I didn't have a way of learning how much an interaction with a medical system would cost me. Now that I live in the UK, I do.

Don't forget profit, and the incentive for insurance companies to care less about what they pay and probably prefer higher prices.

Why would insurance companies prefer higher prices?

Their profit is capped at a percentage of payouts. Pay more keep more profits (after raising rates).