Comment by AnthonyMouse

> There are still huge incentives for doctors to go the US. They can make a lot more money and have a much higher quality of life.

The US limits the supply of doctors by limiting the number of medical residency slots. Foreign doctors are then required to do a US medical residency even if they've already done the equivalent in their own country, which consumes one of the slots. The result is that you effectively can't increase the number of doctors in the US through immigration, you can only change the proportionality in the finite number of slots.

The way for any country to resolve a doctor shortage is to train more doctors, which is the exact thing the US prohibits.