I see. 10 years ago it was also rejected in another feature request here: Ban symbol next to suspended usernames
However, I think the use case I mentioned above (membership expiration as ooposed to banning for bad stuff) is very different from “wall of shame”, so I think this could be revisited. Anyway, one can also make them unmentionable like this: Can I make user unmentionable? - #4 by twofoursixeight
Also, the flair is not displayed when the users show up in search and when you try to mention them. unfortunately:
So with some work, I can make Discourse do what I want. I would of course prefer if it could do it on its own when told. I bet we are not the only ones who would use this functionality.