For those interested in the broader picture, I recommend Aaron Carroll's series "What makes the US health care system so expensive":

https://theincidentaleconomist.com/wordpress/what-makes-the-...

Physician salaries are a part of the problem, but by his numbers they are a pretty small part (as shown in his pie chart at the bottom): https://theincidentaleconomist.com/wordpress/what-makes-the-...