> Users needn't use their real name, but should have some identity for others to relate to. Otherwise we may as well have no usernames and no community, and that would be a different kind of forum.

There's an interesting middle ground here which is to let users specify whatever username nobody else has ever used for their posts. Then they can choose to link them to prior posts (or not) as they see fit. It's not clear to me that this prevents having a community, but I'm not sure what the consequences are.