Why? In the US, if you can pay, you get better care than anywhere in the world. The question is, can you pay?
Obamacare killed the US as a medical mega-power. Economics 101: if you force the same prices for a much larger demand, then either the product sells out, or the service is watered down.
My only experience in Europe is Germany and I much prefer that system over the US. I don't know how it is in other countries.
Germany has its own set of problems but it's still better than the US for most people. The US should compare itself against the best.