When you see old stuffs like this, it's likely that it has been discussed before. Topics like this are usually discussed in Meta board. The best way to get answers sometimes is using the forum's search bar. If you did that you will probably get this result also
Anonymous posting query? Forum History. By reading the comments, you will find the answer
Deleting accounts doesn't mess up any threads, like
this thread. It just changes to anonymous, with no profile information. Post stays intact.
As you can see here, I only change the username to "Anonymous" on request.
Credit to DdmrDdmr -
https://bitcointalk.org/index.php?topic=5193370.msg52775508#msg52775508