Because they would have to get student status and undertake a two year residency, and then take the US medical board exams, and then come over on a H1B and work

Because they would have to get student status and undertake a two year residency, and then take the US medical board exams, and then come over on a H1B and work in a regular hospital (once they'd found one to sponsor them) and then get a greencard so they could work on their own and by then, maybe 10 years after they left India, they would probably be perfectly happy to continue living at the same wages instead of massively cutting their prices.