Imagine you're following a friend of yours and you zap his pubkey all the time, and you even write notes saying that he is amazing person and you agree with him in everything -- then suddenly his key is compromised and his metadata is edited to depict a strong Nazism supporter, now you're looking like a nazist yourself. Does that mean we should have never had the concept of replaceable events and all relays should be storing all metadata events from everybody forever?