One problem with the current deletion is that posts are attributed to "Deleted user". The last-used name, or name at the time the post was made should be used instead, but noted that the user doesn't exist anymore. That helps others that might remember the interaction put the post in context, and allows identifying multiple posts as coming from the same user.

The phrasing common in this community is wrong, it should be "deleted account" not "deleted user" because the user isn't deleted.

In general, any user can always return.

Olin Lathrop‭

The last-used name, or name at the time the post was made should be used instead

No, it shouldn't. I think a better approach would be to use the user's account number (for e.g. user12345 or ex-user12345). This also

helps others that might remember the interaction put the post in context, and allows identifying multiple posts as coming from the same user.

But in a way that ensures the user is no longer identifiable by their previous username. Just like in SO btw.