I'm not sure that comparing absolute amounts between countries makes a lot of sense. And doctors would still likely be in top 1% to 5% also in Europe.
So what are they gonna do? Refuse to treat people and starve themselves to death? They'll be replaced by people willing to earn less and who probably care about the work they do rather than just caring about earning a fat paycheck - those exist, as other countries prove. Seems like a win to me.
Britain had all of these issues and it cost a lot of money.
There's also other issues - like the NHS doesn't cover circumcision unless there is medical need (this is not so controversial in the UK, but would be in the USA), and it does cover gender transition surgery, etc. (despite covering no other cosmetic surgery, and nowadays not covering dentistry or opticians) - all of these issues are controversial and difficult.
It also doesn't cost them a million dollar to become a doctor.
And they don't have to work 80 hours a week.
Doctors in Europe are also easily in the top 5% earners.
Like less than a third or even a quarter of US wages.
That's the real issue - they will never want to take a hit to living standards. It was possible in the UK because it was directly after the war and the Blitz had killed hundreds of thousands of people, and there was a real threat of communism.
Whereas the USA is nowhere that situation today. Things are going very well for the majority of people so drastic change would be very hard.