The US docotor shortage is a myth. Wait times are the result of beauracratic nonsense has reduced the efficiency of the existing physician workforce [1, 2].
In my experience a big part of the problem is specialists. I remember many years ago people were saying that we shouldn't go to a Canadian style single-payer system because Canadians had rationed care and they had to wait six months for a hip replacement.
Well, guess what? I now also have rationed care. I have to wait six months just for a colonoscopy, plus I pay twice as much for the privilege!
Part of the specialist problem is they make so much they realize they can work for ten years and retire, instead of working the 20-30 years that used to be common.
Has nothing to do with wait times. AMA lobbies the government to keep number of seat at med schools low, number of residencies low, etc. as a result number of licensed doctors is low, and salaries remain high.
The AMA has been arguing for increased medical school seats and increased GME funding for about 20 years now. There have been 27 (!!) new medical schools opened in the last 15 years, in large part driven by the AMA in its capacity as one of the two primary stakeholders in the LCME, which accredits allopathic medical schools.
1 out of every 7 medical schools currently active in the US was founded in the year 2010 or after. That's a veritable bonanza in medical school creation, facilitated by the AMA.
[1] https://jamanetwork.com/journals/jama/article-abstract/26132...
[2] https://hbr.org/2020/03/the-problem-with-u-s-health-care-isn...