This is one of the challenge question you may want to ask upon a centralized proof of stake mining process like that of Ethereum, well i don't think this should be a serious concern because the people are used to it already and cannot afford having an alternative, that was the basis for his own project and it turned a success for him, you can realized that together with how Ethereum has been a global most leading altcoin and i don't think this can change anything about its approach from the use of PoS.