In another thread, I tried to show that some lifesaving medical procedures have inherent costs that would put them out of the reach of many people without support.
That's irrelevant.
As long as the expected cost (i.e. the cost times the probability of needing to pay that cost) is within reach, that's all you need. Financial products like insurance can take care of mismatches caused by timing or bad luck. Even with the inflated cost of health care in the US, it is still well within our means to pay for it (in fact, that's actually a tautology).
No it isn't irrelevant, the highlighted portion is where the assumption is wrong for many people. Chronic illness is often a causal factor in poverty as it restricts earning potential for the person and any carers. Poverty is also associated with poor health so the people most likely to need the more expensive treatment are those who are least likely to be able to afford it.
Methinks you're trying to distract attention from your losing argument. Generally, if poor people are suffering from their poverty, the solution is to give them money to spend as they see fit. We don't really do that, unfortunately, but we do subsidize housing, food, education, and medical care for them. So, inability to pay isn't really an excuse, and it sure isn't now that we have subsidized health insurance on the Obamacare exchanges (well, except for those unfortunate few who make between 100% and 125% of the poverty line in states which didn't expand Medicaid.
Regardless, in a free market, costs would come down, so it would actually make health care more affordable to those
who failed to display some foresight.