FaceDeer

This isn’t anything like how validating in proof-of-stake works (at least not in Ethereum’s version, which is the one I’m familiar with). Validating is permissionless. Anyone can set up a validating account, there’s no authority that can reject you.

Who “authorizes” keys to determine if a particular solarpunk miner is sufficiently solarpunk?

No, that’s not how proof of stake works. Or it doesn’t have to, at any rate. Ethereum’s staking token is not a governance token, holding a lot of it doesn’t give you any “ownership” of the blockchain as a whole.

Quite the opposite in fact, if you’re staking millions of dollars worth of tokens then that means the blockchain has millions of dollars worth of your assets “held hostage” to ensure you follow the blockchain’s rules. If you don’t then the hostage gets slashed.