A simpler way to say this, is that both PoS and PoW are useful but in very different contexts.

PoS is when you need hierarchical organisation with skin in the game.

PoW is when you want something that more resembles physical laws. 

The former is fantastic for structuring organisations that require management, leadership and direction. I don’t believe that will ever change, and trying to apply PoW in this context is stupid.

The latter is great for money bc no amount of stake in the money should allow you to change it. The point of money is to have a ledger for the social / economic game of life. To be accurate, it must live where physics lives.