Let me guess: They don't know about LOGINDISABLED, which is used to tell a client that login is currently disabled for it, typically because it's neither using

Let me guess: They don't know about LOGINDISABLED, which is used to tell a client that login is currently disabled for it, typically because it's neither using TLS nor connecting from the local host. https://datatracker.ietf.org/doc/rfc9051/ https://datatracker.ietf.org/doc/rfc9051/ and search for LOGINDISABLED.