So I'm more familiar with how Cardano and Polkadot do their POS rather than Ethereums. In Cardano since the entry level requirement to operate a stake pool is much smaller than it is to do something like Bitcoin mining, it creates a larger number of stake pools. There's also a soft limit on the size of the stake pool that encourages people to spread out their commitment so no one pool gets to large.So at least in the existing POS systems it seems to be working quite well. I'm going to be interested to see how it shakes out in Ethereum because they have to commit their funds. Which is in a way a burden.The more you put into the system for staking the less that you can use.