I wonder if the situation is much different in the US. The health care system is certainly different. One gets the impression the system in the US preys on seniors as employer benefits evaporate after retirement while insurance premiums skyrocket or are denied because of 'pre-existing conditions'.
Things are completely different in the US. Other speculations about the aged here are age independent. To approach the actual problem, you must first replace the word retirement with injury or downsize.
In the U.S. healthcare is a tool for culling. Oh, look - Apple has new products...
Still, your observation is accurate and poignant. The whole purpose of private health insurance is to rob those who are easiest to rob (the old and sick). The problem is that old, sick people tend not to have a lot of money. So, the "genius" behind U.S.-style health insurance is that you can take money from people when young and well (and relatively wealthy) and then fail to deliver the promised services (on bullshit technicalities like "exclusions" and "pre-existing conditions" and "fuck you, you won't sue me because ha ha you have cancer and will be dead before trial date") in their hour of need, when they are too exhausted to fight back.
If U.S.-style medical billing and insurance were pulled on anyone but the sick they would be met with Joe Stack levels of violence on a daily basis.