This is a really interesting post and I agree with a lot of your points. It is not something I see discussed very often, outside niche medical ethics stuff I've read in textbooks or online. We always think about life-threatening situations, but never the aftermath of what happens if a person is saved. Or if a person has a complaint that may have at one point been benign, only for it to fester if it is not treated seriously, eventually leading to life-altering complications.
Everyone focuses on potential fatalities in medicine, as death is always viewed as the worst outcome no matter what. I think there's not as much awareness surrounding what life after extensive medical issues can be like, as popular culture paints the medical institution as an inherent force for good and puts forward the message that patients need to always be grateful if their life is prolonged/saved and not complain about the shots being called in their medical care. This mindset discourages people from speaking up if they prioritize quality of life over life saving measures that may decrease their QOL in the long run.
To their credit, there are some situations where people are allowed to have such conversations, albeit very rarely and typically in situations where a condition is imminently terminal/hospice care is involved. Whenever it comes to ailments that aren't going to kill you necessarily, I think the medical industry severely downplays the effects of chronic, long-term issues.
Much akin to you, I have always questioned the selflessness of doctors and nurses, not only from my own bad personal experiences but studying alongside people who would go on to do post grad medicine and witnessing their extreme lack of empathy. Out of morbid curiosity, I have tried to make myself read forums for doctors to expose myself to the things that make me uncomfortable and to try to understand their perspectives on things, and the way that they speak about patients they deem as less deserving or lower in the triage queue (therefore wasting time in their eyes) is often rude and disgusting.
There's a huge culture of mitigating liability and risk in medicine which I think desperately needs to change. In the US you see people killing themselves left and right or turning to illegal, risky sources of drugs because doctors cold-turkeyed them off opioid pain medication. Do no harm, my ass. I understand that their government is clamping down on certain medications, creating an ongoing situation where people are left to suffer with horrible pain, ultimately leaving some to die as a form of political power play whilst doctors are doing... Nothing. In the UK this same behaviour is also very common, people are left to rot with horrible conditions and given no analgesics or treatment a lot of the time.
My own experiences really opened my eyes about how messed up the medical profession is and how little they seem to care. No matter how many times I pleaded my case to them that my quality of life is poor and I need help, they would refuse to do anything because my situation doesn't follow the rules of a neat, box ticking exercise and is actually complicated. I remember one particularly bitchy doctor telling me I just need to force myself to do graded exercise, before sarcastically asking what did I expect her to do, she isn't a brain expert.
When people are suffering before their very eyes, they don't seem to care unless there's a palpable chance that death is imminent. Imo there's many forms of protracted suffering in life that are far worse than death. I don't see how they can think otherwise, but maybe they are blind to how their patients are struggling in the day to day.