Ultimately, old people need help with ~everything. A stack of dollar bills cannot care for you; it can only be used to pay other people to care for you.

If there are insufficient quantities of younger people to care for all the old people, no amount of money causes the system to work. Quality of life will go down.

Unless we figure out how to get the robots to do it.

Okay so what are you going to do when you get old?

Oh by the way sorry and afterthought. My mom is actually cared for in a facility where young people are getting paid with money -- actual money -- to care for her. So it seems like in your model young people would work for free? A job is a job no? Anyways she paid lots of taxes and lots of retirement and so it seems that that is working out. Just a thought.