It was an interesting read and reminded me that democratic socialists arguing for restricted capitalism and communists are often arguing for similar goals with differing language.
The main argument is that that would not less to democratic control. Are there any historical examples where you have both democracy and violation of private property rights?
I think decentralization of power is a nice feature too. Billionaires are power centers outside of the government, judiciary, or military. They exist as a result of lax control on the markets by the government. In countries without capitalism and property rights, the billionaires are the government and the judiciary and the military. So, even though it might seem like nationalizing their wealth would decrease inequality, if there aren't good safeguards for decentralizing government power, it would result in a less equal society.
Part of the existence of billionaires is the ability to actually determine which money is theirs. In autocratic governments, you can't really say who owns what because you never know what the government might decide to take.
I don't defend billionaires, I think power should be spread more fairly, but eliminating them via the government needs to be done wisely in order to maintain decentralization.
Why would you wash your towel? Your towel washes you. That's like cleaning your shower.