And who exactly, historically lobbied for that low limit to limit doctor supply? Why the AMA and other similar organizations!

And these kinds of issues seem more global than not.

True, but the AMA reversed its position some years ago and has been lobbying Congress for increased Medicare residency program funding. However, Congress hasn't acted due to budget concerns.

The last time the AMA lobbied for capping residency slots was almost 30 years ago. The vast majority of doctors practicing today weren’t even in the field back then.

That may be true, but insurers continue to lobby for capping, and in the US most large employers are "insurers" in the sense that although they might outsource the administration of the health plans of their employees, they basically pay the entire cost of the care.

Although doctor pay is only a small fraction of the total cost of health care, limiting doctor availability is an effective way to limit total cost because most expensive health care goods and services require a doctor to order or prescribe the good or service. I.e, until the patient gets enough time with the doctor for the doctor to realize that the good or service is necessary, the insurer does not need to pay for the good or service.

Stop lying. No major commercial insurer is currently lobbying Congress for limiting the number of physicians. In fact, some insurers have even voluntarily donated to support residency programs (although the amounts are small relative to Medicare funding).

OK, I now tend to believe that when the ACA capped the profit margins of insurers, their previous incentive to reduce cost of care (so they could keep the savings as profit) ended, so they stopped lobbying for restrictions on the supply of doctors. Unless I see evidence to the contrary, I will continue to tend to believe that large employers (not subject to any cap on their own profit margins) continue to lobby for restrictions.

I tend to believe this because of how strong the correlation has been in my own "career" as a patient between my ease of access to doctors' time and how much my insurance plan ends up paying for tests and treatments.

How would restrictions on the supply of doctors help insurance companies reduce cost of care?

Limiting doctor availability is an effective way to limit total cost because most expensive health care goods and services require a doctor to order or prescribe the good or service. I.e, until the patient gets enough time with a doctor for the doctor to realize that the good or service is necessary (then prescribe or order it) the insurer does not need to pay for the good or service.

Limiting the supply of doctors will increase costs in the long run because it reduces access to preventive care. Residency caps disproportionately impact PCPs.

It might reduce the costs they pay for preventive care or non-urgent care, but serious issues will progress.

You might not have to pay for metformin to treat diabetes, but you’ll eventually end up paying for a hospital stay and amputation.

You don't have to convince me that limiting the supply of doctors is not in the interests of anyone of median income or lower. I am aware.

Your proposed incentive for insurance companies to want to restrict the supply of doctors (prior to the ACA) doesn’t make sense, and that’s what I’m trying to convince you of.

Ah, I see now. Sorry for not getting it right away.

Nope, there are no major self-funded employers lobbying for physician caps either. But hey, don't let facts get in the way of your ridiculous, uninformed beliefs.

I’ve never heard of insurers lobbying for capping residency slots. Do you have any sources?

Regardless I was responding to the claim about doctors lobbying for caps.