>If there was a dramatic increase in the number of medical schools

The bottleneck for the number of doctors is residency slots, not med school slots. If you drastically increased the number of residency slots med schools could rapidly ramp up to fill them. If they couldn’t fill them foreign doctors wanting to work in the US would.

Beyond funding for residency slots. The real limiting factor is the number of doctors willing and able to train new doctors. Even if your plan is to product dozens of new kinds of practitioners, doctors are the only ones qualified to train the new practitioners today.

In a hypothetical world where you say “I want to create as many doctor equivalent practitioners as possible”, there’s no advantage to creating new types of doctors because existing doctors are still going to be the bottleneck. Essentially if you create a new PA program with a residency, past a certain point, you’ll just be competing with med schools and existing MD residencies for the same resources.

>whether or not X training in Y field is actually necessary or if it's unnecessary overhead

You know who spends far far more time thinking about this than you or I? Doctors like my wife who is the director of medical education for her division. Her and her colleagues are constantly evaluating resident’s performance and if anything they think that most of them could use more time not less. Her specialty is so overworked and understaffed that every doctor in that speciality would drop a year of residency if they thought it was feasible.

Doctors have strong a culture of service and the peer pressure to serve the community and put the needs of public health and medicine in general above their own is immense. I’ve never seen anything else like it in any other profession that I’ve encountered. I certainly don’t think that Doctors should be able to regulate every part of medicine with no oversight, but I can’t think of anyone more qualified and deserving to determine how much training is necessary to practice.

I’m not saying there are no inefficiencies here, but given the amount of time and effort regularly spent on resident education, I strongly suspect there are no large savings to be had here.

>current residency practices might even decrease patient safety in a lot of ways

Most of those claims have been debunked. Numerous high quality studies have shown that adding limitations to number of hours residents can work and limiting shift lengths did nothing to increase patient safety.

>just they also tend to have lower scores etc and have long respectable practice

Foreign medical schools that attract US students tend to have very low placement rates. If only the top 60% of your students match, you can’t look at the average student score and compare it to the average student score in a US school where 95% of students will match. If you look at actual residents who went to a foreign school as opposed to looking at average scores of everyone admitted, there isn’t a big difference.

As for DO scores. They are lower, but by a very small margin. Nowhere near the difference in scores between PA and NP students and med students.

It’s hard to compare them directly because PA applicants take the GRE not the MCAT. But the average med school student scored north of the 80th percentile on the MCAT, while the average PA student was right at the 50th percentile on the GRE. And college GPAs are much higher for med students.

>cost multipliers due to lack of options

I don’t know that this is the case. It could be but I suspect it’s not for a few reasons.

I’d expect any bottlenecks to already be reflected in the physicians salary. That is they would have captured a fairly large part of the increased price in their salaries because by becoming they bottleneck they are now more valuable.

We have been increasing the number of physicians per capita since 1960, but healthcare costs have been rising. If you look at list of developed countries by number of physicians per capita and compare it to a list of counties by healthcare expenditures per capita, there’s no correlation. if physical bottleneck was driving a significant chunk of healthcare costs, you’d expect to see a correlation.

>patient satisfaction due to increased choice

Patient satisfaction is so strongly correlated with whether or not a provider prescribes you something that it’s mostly a useless metric. It’s well documented that NPs and PAs are more likely to prescribe unnecessary antibiotics.

This leads directly into another issue I have with increasing the types of providers. Creating additional providers with their own governing bodies creates administrative overhead with significant costs.

Over prescribing antibiotics is a prime example. We’ve decided this is a problem, but now you need to convince med schools and residency programs to, np schools, pa, schools, and whatever new providers are created in this hypothetical world.