Both PoS and PoW are useful in different cases, PoW for resource allocation in a network where mining rewards useful work and resource contributions, PoS for allocating dividends and voting with proxy for investment funds and other applications for pooling resources.
Since Ethereum is a computing platform, and not a distributed corp, that would suggest that Ethereum would benefit more from PoW's contribution of useful work and mining resources, as opposed to PoS's earnings, dividents, and voting from speculative holders. Thanks for further clarification.