We're not selling lies to folks with more money than sense, therefore there's a ceiling on most doctors potential earnings.
Most of our "clients" are not wealthy and wouldn't otherwise be able to afford the medical care they're receiving. Even if that care is worth "a lot" to them, they simply don't have much to give. Heck, the U.S. spends ~$8B annually on the hospitalisation costs from firearm injuries – think about the trauma systems needed to support that sort of emergency, surgical, and critical care – for folks without the means to pay for it. Same goes for elderly, nursing home, dementia care, disabled, etc.
Not a rant about whether those folks "deserve" medical care, but that healthcare – in other countries moreso than the U.S., but still in the U.S. to some extent – is more a fundamental public service, like buses and sewers, and the general public will only fund to the bare minimum possible. The principles of "supply and demand" don't completely apply to the health sector because there's a disconnect between "demand" and the willingness/ability to pay more – because blue collar, government payor, etc. (even before for-profit insurer cartels are factored in).
A long, roundabout way to say – no, general physician salaries will not keep up with the private sector.