When it comes to governing blockchains the same rules need to apply. Any single metric, whether proof of stake or proof of work will become dominated by an entrenched few who are most adept. This is why blockchains should be governed by many different proof-of-work, proof-of-burn, proof-of-stake, proof-of-person, proof-of-location, etc. The more pareto distributions and the more independent those distributions are the more decentralized the network will become.