Frostr is the only interesting option.

How would your alternative protocol handle the key rotation without single central entity?

Frostr isn't key rotation in the base sense he seems to be talking about though. It's still a single forever-key, just one with several minions.

please don't 😭 just separate identity from authorization:

GitHub

NIP-102: Subkey Attestation by ynniv · Pull Request #1450 · nostr-protocol/nips

This NIP defines a way to separate identity from authentication using hierarchical deterministic (HD) keys. This allows people to use one key pair ...

Sure, but if you use different keys everywhere, you just need to rotate those keys, not your main one. There will never be a rotation of the main key.

Dunno but I think he means rotation of the main key, hence the to-fork-or-not-to-fork internal debate. As in some fork where a majority of the guardians can sign a transaction to replace the lost main key with a new one and the protocol respects that. Farcaster sort of does this.