Inequality arises naturally out of many different processes. You can think of the economy right now as being Pareto optimal or efficient; any reallocation of capital will necessarily make one person worse off than another. It is an example of the power law distribution.
> Put a 90% tax on income over $1M, make 20 hour work week / 12 weeks vacation the new standard, introduce a land value tax, make it impossible to hide wealth offshore, and find a good way to distribute all the extra revenue so that people don't starve but still have just enough incentive to work (in a world that needs much less work because of automation). That'll go a long way towards fixing excessive inequality in a heavily automated world. Half of this can be done to great positive effect even today.
That sounds to me like the way to hell paved with good intentions. If you increase the tax rate to 90% over $1M, those individuals will simply move their assets elsewhere. What's stopping them from investing in real estate in Japan (where you can still get good deals, because the dollar is still relatively strong, even though it soon won't be)? Wealth redistribution sounds nice in theory, where you can feel good about yourself because hey, you're saving the world right? Except you're making things worse. All those wealthy individuals you want to heavily tax will stop hiring here, and suddenly you have a population of very angry people that cannot work anymore. The illusion of a living wage is better than no wage at all.
The conclusion of the article, to me, is that the concept of a central bank and a State is obsolete. The future is rich city states with zero regulation, Pareto optimally efficient economies, surrounded by wastelands of those left behind. This is what the Singularity entails.