It also certainly defeats much of the original purpose of decentralization when a few stakeholders have total control of the network because they hold the most coins...
Regardless if the network has "correct incentives" or not, things can happen to those stakeholders outside their control, or other incentives could easily develop to act in bad faith against the network.
As opposed to a few stakeholders that have total control of the network because they hold the most computational power?
And before you bring up mining pools, you can replicate that in Proof of Stake by creating staking pools.
Lol. And we're just supposed to believe you, right? Show me one POS which is as secure as POW.