The point is that complete post scarcity isn't really a possibility by any theory we know. Now you can make a sci-fi argument for post-scarcity ala-Star Trek. But as far as economics is concerned, it's so far out there that it isn't really even a theory. Just a fictional 'possibility'. Which is why I didn't get involved in the thread earlier. Outside of a scifi story, I can't imagine it. And even within a scifi story, there's still only so much frontage on Miami Beach.
Complete post-scarcity is not really possible any time soon on this planet.
However we have virtual post-scarcity on some non-tangible items.
Imagine all the music, games, virtual items inside games, etc.: they are for all practical matter unlimited.
It costs to create any of those "virtual items" listed above, but once produced the cost of duplicating and distributing them is extremely low (close to zero for very large scale distribution).
This type of economy has most if not all the characteristics of a post-scarcity economy.
At the time being the issue is solved by imposing an artificial "scarcity" on the items by enforcing copyright laws, DRM, exclusivity (e.g. CivV only from Steam), etc.
In this way they can still work under the traditional market economy, reap a large profit on sales, and as a side effect motivate (pay) people to create more "virtual items".
In this case scarcity is artificial and, however we may despise it, it allows people to still innovate and produce always new "stuff".
What will happen if we would remove this artificial scarcity (e.g. allow copy and free distribution of any "virtual item")?
Would it lead to a complete collapse and stagnation or the system will find an equilibrium with some people still producing "virtual items" just for the fun and prestige of doing it?
In the real life we live probably we will have a considerable stagnation: people still have to have a revenue to pay for their needs (e.g. food and house) so they can't dedicate all their time to activities that bring no money at all.
But if we imagine a truly post-scarcity society where people can get what they need to live without having to really pay for it and equal access to respurces, then they will also have no need to spend time in activities to pay for their living but they will have time to create new stuff (invention, research, new songs, anything) just for the fun of doing it (and probably for reputation).
In my view even if we imagine a society with de-facto unlimited resources there will also be some form of scarcity.
The scarcity may be only temporary (e.g. enough ice-cream for everybody, but if you want chocolate you have to wait one day, pistachio is available immediately) or some new form of scarcity.
Unfortunately every time we try to imagine a truly post-scarcity scenario, sooner or later we hit some limitations.
We could imagine we have mastered some super-advanced technology to produce energy (virtually free, clean, and pretty much eternal) everybody has his own nano-replicator, unlimited access to blue-prints of everything existing, and access to energy.
Even in this scenario we may have an element of scarcity: raw material.
However automatic crawlers (built free by replicators and powered by our unlimited energy) that scout our planet and near planets/asteroids will provide the raw material.
Maybe if one resource is requested by too many people, somebody will have to wait.
Maybe inventing new stuff will allow the inventor to have "credits" to have priority access to (temporary) scarce resources.
In this case, then, "credits" will be the element of scarcity and people will work to gain more of them.
A post-scarcity economy but with a rather arbitrary element of scarcity.
