"But until we can learn the unavoidable truth that all retirees, without exception, live off the currently-working, the simplest solution to retirement will remain forever out of reach."
Ho. Ly. Shit.
I can't even come up with words to describe this statement
I think you are misunderstanding this statement. What he is saying is that retirees depend on real resources - food, energy, housing, etc. - that must always be provided out of current production.
In order to have a percentage of the population not working, those that are working must produce enough to not just provide for their own consumption, but also for those who are not producing (children, retirees, Knights and Lords (if you're into the whole Feudal thing)).
This transfer always has to happen, but can happen in different ways - in the absence of any money, there could be direct confiscation and redistribution (a la the granaries of Ancient Egypt). There can be taxation and transfer payments. Or there can private investments that pay a return. Underneath it all, the same transfer is taking place - there is production over here, and consumption over there - it's just the mechanism that changes.
This is what drives some of us mad about those who say "Social security is going to go broke because there won't be enough workers, so we need to have private accounts!": as long as there is enough surplus, we can support retirees - and if there isn't we can't. If "there aren't enough workers", we would no more be able to feed everyone via "private accounts" than via Social Security (mmm, yummy stock certificates - I hear they go great with a side of broiled bonds!)
Fortunately, we will be able to feed anyone (barring catastrophe), even with a declined number of workers - the estimates I hear are that somewhere around 10-15% of the current workforce grows all the food, builds all the buildings, and manufactures all the goods that we use - the rest of us mostly sell stuff back and forth to each other. As our robot overloads (who I, for one, welcome!) take over, this will only decrease. So what percentage of the necessary redistribution going forward will be done via taxes and transfer payments vs. private savings is a political decision, not an "OMG! Trust fund! Broke! Cat Food!" crisis...