In every case costs have gone down and outcomes have improved.
You always build on what you have because you can’t pause healthcare for very obvious reasons.
Hence a lot of different systems all with the same aim. Controlled costs and universal coverage.
The idea the US is somehow different and cannot make the change is the result of propaganda and a mistaken belief that the current Us system is the worlds best despite its costs.
Healthcare reform is easy and there is an ocean of prior art.