the world has changed alot. I mentioned in another post how the political problems of the ancients have taken on new dimensions in the modern world of nation-states. but that doesn't mean it's irrelevant. many of their concepts and ideas are still valid, and human nature hasn't really changed. even their political questions are somewhat relevant, they just have to be considered in their different context. I believe that providing necessities to everyone is much easier said than done. for example, the european model of socialism has been going through a crisis in recent years. and even when all is well, new burdens and problems crop up when you shift away from capitalism and towards socialism. I'm not sure what you mean by post-scarcity. there will always be scarcity, even if it's reduced to a negligible level. A society of overflowing abundance would be excellent, but that is not viable while we're all on one planet.