Not that I disagree with you, but as US society, and AIUI many other modern societies, are organized around a growing population. In order to have Medicare and Social Security in their current forms, you need n increasing number of working age people to keep the programs solvent.
Changing this, and moving to a society where AI and robots solve the problem of letting people retire (presuming that's possible, technologically) would require a massive shift in how people are, for lack of a better word, valued by society. Right now, we assign a lot of value to individuals based on their level of economic productivity.
It would be a change of considerable magnitude to let AI and robots create the economic value and then distribute it to individuals on some "fair" basis. I suggest that based on the current situation, finding agreement on what constitutes "fair" would be challenging, at best.