The hip replacement can be covered under another policy like a home warranty. At the same time, without coverage, the prices have to come down. If they don't, all of those expensive doctors are bringing in near $0. Such an economic position is untenable.
The other two are probably going to be fixed through direct market forces. If the people of America can only pay $X, then the makers of the drugs can only charge $X + small premium to have a market. Since they would face a similar price pinch abroad, they'd have to adjust their prices.
We've seen the inverse of the price pinch with the epi-pen scandal. The makers knew the price could go up since insurance would absorb the cost.
Hiv cost over a lifetime is only 340k and 1:300 in the US has HIV, so the subscription would only have to cover a little over a 1k in lifetime risk; actually less, since HIV is overrepresented in the homeless and poor segments.
How would such a model handle predictable-but-expensive medical needs, like hip replacements for the elderly and monthly prescriptions for HIV and cancer patients?