The cost to become a doctor is now so high in the US that you have a tremendous amount of debt and have to charge high to pay it off. It’s also why no one wants to become a GP.
Doctors really are not that highly paid outside of speciality practices these days. As you note, GP is the last resort for most largely due to this reason.
Many on HN make more than physicians these days. Doctor pay is not the problem in US healthcare and hasn’t really ever been.