Well, the AMA does constrain the number of doctors in the US so that supply and demand part is on them.
MBA hospital administrators have greed as their official main job responsibility.
The average physician salary in 2023 is $352K. I wouldn't say that.
The big DI manufacturers have consulting arms that will help physicians with financing to buy CTs, MRI, PET, that will help them obtain Certificates of Need.
And having a hard time finding it now, but physicians who own a share in a DI lab tend to refer their patients for imaging far more generously than those who don't...
Then compare how much Medicare compensates doctors compared to compensation in other countries.