No... it is that human wickedness being what it is, the main sick desire of people is to be a little god, and that means being worshipped by one's neighbors. But it also means being able to rule them, to punish them, to enforce one's own view of justice on them. I see that every day, in that those who haven't recognized their wickedness and begun to battle it, really collide and irk each other. Those who *do* have power lord it over the others; those who *don't* have power get incredibly angry.
More than that, those who do have power actively work to destroy those who don't, while at the same time, criticizing their victims for not wanting better for themselves.
So if you give people a utopia, what are they going to do with it? They'll find a way to fulfill themselves. That means, they'll find a way to fulfill their wicked desires. Now, yes, the woman in the story goes on her little vacations to do exactly that, and it gets her excited... but that is not the only way wickedness plays out. And where there's a will, there's a way. People will find ways to destroy each other that are "under the radar". No computer can outdo a human in creativity, especially when the goal is so illogical (but makes one feel oh, so good).
Moreover, what doesn't feed the wickedness isn't going to give a person motivation. So again, the society isn't going to magically progress. It might devolve into computer games, where people can play out their fantasies, or board games, or sports... but it won't progress.
As to your point about the manna system being fully practical and possible, I'm not so sure about that. It seems to me that scheduling is NP-hard. So, if your manna system is going to "perfectly schedule" the business, it'll fail. However, if it's going to be "pretty good", then it can possibly succeed.
But it also could well fail in another way: what the author describes would surely lead to destruction of the systems and civil disorder, even civil war, long before it came to welfare tube-house prisons.
Moreover, every single manna-run country would be ripe targets for crackers (and how would taking out an entire nation of smug billionaires do for a person's wicked desires?) or conquest by military might.
Moreover, as a government's laws destroy an economy -- and these employers in the story are governments unto themselves -- they drive a black market. The black market is going to drive crime, which will eventually overwhelm the nation.
I don't foresee it happening the way the author says. I do foresee it possibly starting, though.