In Nostr, NIP-51 outlines that the mute list is stored within the 'p' tags. The content part of the event can be encrypted to keep another list of mutes private. Therefore, a person who is muted may not be able to identify that they've been muted, especially if the content list is encrypted.

However, keeping mutes public has its own pros and cons. On the positive side, it enables others to aggregate those mutes into their own lists, which could be useful for community moderation. On the downside, making mutes public comes with the risk of causing social tension or discomfort among users.