I agree you should be paid properly. But I don't understand why, if the US has a privatised healthcare system, hospitals are not paying to train their own labour?
US hospitals are almost all nominally non-profit. In practice, they are partnerships run for the economic benefit of controlling employees but the scam the tax code by pretending otherwise.
They do to a degree but most of the money comes from the government to subsidize costs. I’m not privy to the amount or percentage but they do cry about it when the residency union (CIR) asks for inflation adjusted salary increases.