Vitalik Buterin didn't anticipate that PoS leads to oligarchy. Central planners, well-intentioned or not, usually don't anticipate the failures of the markets they create.https://twitter.com/VitalikButerin/status/1011248080652570624 …
PoW leads to unsustainable arms race.
PoS/DPoS leads to plutocracy/oligarchy.
Decentralization gravitates towards centralization. Pareto principle applies to #blockchain consensus mechanisms.