The historic unemployment rate for physicians in the U.S. is <1%. The historic unemployment rate for science PhDs in the U.S. is <3%. I am not sure where you got the data to make the claim that there are no jobs for science PhDs, unless the only jobs you would consider are tenure-track positions at Harvard, MIT, and Stanford.
I am a practicing physician that saw the light years ago and decided to go back and get a STEM PhD. I know exactly zero unemployed science PhDs, and all of them are happy in their careers, which are at research universities, research institutes, big-tech, big-finance, consulting firms, biotech, and start-ups. They are treated with dignity and only interact with other intelligent people at work. None of them ever talk about wanting to quit or retire early. I get to experience this as well during every moment I work on research.
Conversely, every doctor I know (save 1 Urologist), and I know hundreds, wants to quit medicine immediately and regrets ever becoming a physician. This spans Intensivists, Cardiologists, Neurologists, Nephrologists, Radiologists, Ophthalmologists, Pediatricians and Emergency Physicians.
Sadly, none of these doctors have any marketable skill or way to make money outside of clinical care, so they all chase the FIRE pathway in hopes of retiring as soon as possible. None of them are older than 40. None of them have any hope for a meaningful career in medicine.