Stalin and Brezhnev did NOT allow the wealthy industrialists and landed gentry to keep their private wealth. On THIS score, Hitler is much closer to American free marketers than Communists or Socialists.
Hitler allowed the industrialists to keep their wealth, provided that they did his bidding. This was a state regulated economy where the penalty was death. It has nothing to do with a free market system. In virtually every way, it is similar to the soviet model. Per the article:
Under communism, there is collective ownership of property DEJURE.
Under Nazism, there is the same collective ownership DE FACTO.
It is a difference without meaning in this context.