One is you need a medical license to practice. To get a license, you need to be a graduate of an approved medical school. Slots in medical school are controlled by the AMA, which has a strong interest in limiting the number of doctors being minted, to keep doctor fees high.
Part of the reason behind restrained increases to med school spots is because traditionally they tried to get very close to full placement to residencies. In recent years, med school attendance has grown much faster than residencies, and that would be a very terrible position to be in to go $400k+ in debt and pass med school to only get stuck when you don't place into a residency the first round. https://www.aamc.org/news-insights/us-medical-school-enrollm...
EDIT: There are also separate osteopathic graduate schools and foreign med schools (Caribbean) that aren't limited by the AMA and still funnel thru the same match program.
> I know a trained foreign surgeon who switched to law after immigrating because of this red tape.
I had a few of my undergrad bio and chem labs with a Vietnamese doctor who came to the US, I always tried to be in his group whenever possible because he had the most insight into the Industry as a result of his transition.
Apparently, because he was educated and practiced in Vietnam he was forced to have to repeat the entire process to enroll into Medical school. I'm not sure if was on loans or doing it on his own, but he must of have been determined to make it happen, because I'd probably do the same as your colleague if forced to do it all again.
He was an older guy, I was 18 or 19 so anything over 25 was 'old' to me but I think he was in his 30s while we were in our 2nd year courses.
With all of the polemics surrounding COVID19, I think the least we should do is take away the power of the AMA-like Institution to determine how many medical students can be enrolled into any program and make any necessary accommodations to ensure it happens.
Making the current medical staff do the equivalent of an understaffed, under supplied death march has to make reason prevail regardless of our stance.
Private and Public medicine is an issue to come back to, but being short staffed in a pandemic is suicidal--Italy recalling retired medical staff was alarming, but also highlighting that a Public Medical system is not yielding the panacea many suggest, either.
And for anyone asking for a source on the AMA's practices look at his, I remember reading this in 2005 as I was in school, and being schooled and trained as if I wanted to take MCAT because of the looming shortages caused by retiring boomers, even though I had no interest in Medicine:
That's just one.