We have a critical shortage of doctors in the US because we have a population of 330 million people needing care, but too many people who want to be doctors can't afford to make that investment of money and time to become one. Then there's the problem of even more of our population being too fucking stupid and/or lazy to get through medical school. Both factors create a deficit in cranking out new doctors to keep up with the population growth.
Meanwhile, the stupid people want zero immigrants, the only way to get any of the smart people in other countries to come here, either to get the education to become doctors, or, if they're already doctors, to bring their experience and expertise here. If that's not enough, the stupid people hate hate hate that the doctors or future doctors who are willing to come here to help us out aren't lily-white Europeans. The stupid people are too fucking stupid to realize that it's the rare European doctor who wants to come here, when he can have a superior quality of life right where he is.
So our doctor:patient ratio continues to plummet, adding to access woes already abominable thanks to high costs making health care available almost entirely for the fabulously wealthy or well-insured.