[rstuart4133]

> Proof of stake entrenches a group of rent seekers in perpetuity,

Ahhhh, that's a light bulb for me.

PoS is a step backwards in security, but perhaps not a meaningful one. Bitcoin has proved itself to a rock, or possibly a mountain range when only a rock is needed.

But yes, Bitcoin's mining fees are very carefully structured to be a near perfect market. Not so great for the miners - but perfect for the currency and it's users. Now you mention it, or Ethereum PoS looks like an excellent mechanism for the dominant Ethereum holders (which includes the founders - a point I'm sure hasn't escaped them), to entrench their position. I think we can safely predict things will take their natural course over time - and they will start charging what they think the market can bear.