I'm having a hard time understanding why they would be bitter. Residency is temporary and a part of the training process. Once completed, doctors will make 2x-3x+ compared to midlevels for the rest of their careers.
Residency has a lot of problems. The match is stressful enough. Medical school graduates carry a huge amount of debt, but must complete residency before earning enough to meaningfully pay it off. Residencies pay 40-85k and most resident physicians are expected to work 80+ hours per week. 80 is the theoretical maximum, but that doesn’t count time arranging work, studying, taking board exams, etc.
All this, and if you don’t complete your residency, you have no prosperous future as a doctor. You might re-match to another residency if you’re very lucky. The hospitals know this and act accordingly. Residents and even medical students paying tuition (!) were assigned to treat COVID patients and couldn’t really decline without risking the future they’re heavily invested in.
Keep in mind, the federal government pays ~150k per year to the hospital for having the resident. Yet the residents are often more indentured workhorses than trainees. It’s not uncommon for entire departments to run overnight with only residents, but no attending physicians.
Now imagine being in this situation, and not being allowed into the “providers lounge” because you’re a resident. Or using a broad-spectrum antibiotic instead of something more specific and being scolded for poor antibiotic stewardship, while the NP who has “completed their training” can’t even properly decide antibiotics are indicated some of the time. And if that NP were ever treated the way a resident is, they could go get a job at the hospital on the other side of town and start in a week.
Because the future is for doctors to not make 3x compared to them. The mid levels are being used to increase supply of healthcare, using the doctor’s license for liability, in order to reduce the price doctors collect (per unit of time and effort).
Basically, they are watching their expected wealth / purchasing power be reduced.
If someone was making more than twice as much as you, working half as many hours as you, seeing half as many patients as you, and were less qualified for their similar role, you would be upset too.