I use "display" name (doesn't need to be real) and it doesn't create the expectation of uniqueness
Discussion
how do your mentions appear inline, with display_name ??
💯
What’s the best way to pull your name up in Damus when typing a note? That’s all that matters here for client compatibility.
display_name is an unspec’d damus field meant for just a way to show a real-name on your profile, the fact it is now required for cross-compatible mentions is a bit annoying.