Quote from the article:
there are plenty of reasons to believe that we may be at the beginnings of a post scarcity economy. We have a surplus, no doubt. Of course, we still have legions of people in the world that are starving, and even people still here at home. But we actually have the capacity to feed them, to feed everyone, even now, even if we don’t have the will. It’s not a matter of scarcity; it’s a matter of the organization of labor and capital.
The problem here is that there is no "we" that can implement this unrealistic plan of arranging for an easy living for everyone. We're all just individuals and pursuing our personal gain, as I mentioned. That much is constant, because it's how we're biologically wired to operate. So, there is no "collective we" that could decide how to run a society, but that's exactly what he's suggesting.
Of course, the only entity that makes collective decisions is the government. But the government only has one way to affect an economy: coercion. In essence, this guy is suggesting that governments should force some people to provide for other people. It's just another version of "welfare", but any kind of welfare system is about using force and coercion to re-allocate resources, because otherwise resources would just get "allocated" through voluntary exchanges. In reality, it makes no sense to talk about some specific "allocation" of resources, because the only way you can even try to achieve that is through coercion again. Coercion is immoral and forbidden though, so you have no business trying to effect any specific allocation of resources.
In addition, there's a gross mistake at the root of all this: the idea that you know how resources should be allocated. We're already covered that without coercion, resources will just end up where ever they may, and that's just the end result of countless people pursuing their personal gain, making the exchanges they want to, and so on. You are only your own personal self, and you don't know what kind of exchanges other people should go through - it's all subjective.
In summary, people talking about "post-scarcity" or a "resource-based economy" (Zeitgeist) and how those should be arranged, are basically engaging in central planning, and they either realize it would require massive amounts of coercion or they do not. In the first case, they're just plain evil, and in the second, they're clueless. Either way, what they want is impossible.