That's a valid point, but PoW has other problems, which I'm sure you're aware. With Bitcoin, as an example, we now have to trust the large mining firms/guilds not to collude together for their own benefit. We have to trust changes will be implemented that benefit everyone instead of being stalled by the powerful. I remember a point in time where a large mining guild decided to split up (against their own short term interests) because the community was too concerned with the percentage of hashing power they controlled. I was glad they did it, but it reminded me how much trust is still involved in PoW as well, even if it's trust that those involved will remain rational actors for their own long-term self interest. At least with DPOS there's a mechanism for making that trust transparent with a voting process everyone can participate in.