The AMA issue is not new. In “capitalism and freedom” 1962, Milton Friedman wrote that it will turn into a cartel, then it did.
They have their own interests to protect, and those interests aren't 100% aligned with the medical needs of the American population at large, nor with doctors struggling to make ends meet after taking on a ton of debt to go to med school.
Is it any wonder that those who enter med school (or residency) with a deep sense of altruism get burned out rather quickly? I think not.