> Users may register for accounts and provide their public Ed25519 keys. Later, when they wish to login, they sign the string "login" (with their private key),

> Users may register for accounts and provide their public Ed25519 keys. Later, when they wish to login, they sign the string "login" (with their private key), base64 encode the result of that and provide it to the server. The server then verifies the signature using their public key. If it verifies, then the user gets a session. How is this not just a more complicated password? Usually these sorts of protocols have some sort of challenge for the client to sign, making the login one-time and checking that the user actually has the private key.