If your implication is that this is a private vs public spending problem, that's not it. Healthcare in the US (both private and public) costs dramatically more than in other developed countries.
Why that is is a bit complicated and doesn't have a single root cause. It's also a bit tricky because every major component blames the other components for the total cost.
Part of the problem (roughly 10% by one estimation I read) is drug prices. Drug prices in the US are >2x the price as compared to other developed countries [1].
> If your implication is that this is a private vs public spending problem, that's not it.
No, my point is that we couldn't achieve UK costs by doing "single payer." Our publicly funded systems, like schools and transit, are also cost-inefficient (public schools somewhat less so, public transmit somewhat more so).