I've actually mostly given up on proof-of-work blockchains.
At the end of the day, I'm not interested in authority-from-compute. I'm interested in authority-from-the-people.
The best use of blockchain technology I can see is as a collective tool which enables us to implement lots of things in society better. Much like the internet enabled thorough improvements in society - most people don't know how the underlying technology works, but it makes their lives better. And I think blockchain technology can do some of that too. It can be the backbone on top of which we can build lots of things which make society better in one way or another.
The thing is, a society has to have some way of issuing unique identities and proofs-of-existence to its citizens, to tally votes and the like. This can be as centralized as it is now, with government bureaucrats issuing identifying documents and updating records when people die, or very decentralized, like a network of people staking their own reputations to vouch that some other identity is a real person and that some real person has died.
But however you do it, once you have a system for linking each person to one hard-to-fake identity, then you can build a blockchain under the assumption that every person has one identity, and that these identities cannot fall in large numbers into the control of bad actors.
And while that assumption lets us improve proof-of-work blockchains, I think it also lets us just not do any proof-of-work in our blockchains.
