Triage, whether by overworked nurses or by auction or by private death panel or by public death panel, is not necessarily a problem created by administrators. It can be created by having too few surgeons, in which case whatever caused that (in a time of peace, no less) is at fault. Last I heard it was the doctor's guild lobbying for a severe crimp on their training pipeline, in which case blame flows back to some combination of doctors and legislators.
You heard wrong. While at one point the AMA lobbied Congress to restrict residency slots, they reversed position some years back. However Congress has still refused to increase Medicare funding for residency programs. This is essentially a form of care rationing imposed through supply shortages.
https://savegme.org/
There is no "doctor's guild". No one is required to join the AMA to practice medicine, nor are they involved in medical school accreditation.
Like I said, some combination of doctors and legislators. If doctors lobbied the laws (or budgetary line items) onto the books and they are still in effect, they still have culpability.
Blaming congress too is fine, but let's be clear: someone has to fight to increase every budget and the AMA didn't just know this when they were structuring their proposal, didn't just count on it not happening, they considered this an implementation detail subordinate to the openly admitted primary objective of propping up physician wages as the Greatest Generation passed. That was always the goal, they were extremely open about it, and about 15 years ago I was attending a talk on demographics in medicine with a primarily physician audience, one of them asked what the plans were to change this to staff up for the Boomer wave (the bump was on the slide, begging the question) and the presenter waved his hand and said maybe they could do something... or not, and then he laughed, and the rest of the room laughed with him.
I'm glad that the AMA has changed their stated position now that it's too late to change course (for the Boomers anyway) and their squeeze is bearing fruit for them and suffering for their patients, but I'll always remember that room full of doctors and doctors-to-be laughing about the prospect of intentionally understaffing for profit. I have it filed in my memory right next to the phone call of Enron traders giggling as they ordered power plants offline to scare up prices, except it's about a million times worse.
I'm not even talking about triage. It's not a matter of who has the worst problem, it's about which patient the nurses deliver to the surgeon and anesthesiologist. Literally just who gets scheduled and when.