Is this a bug or just something you did accidentally?
Is this thread type a new discourse feature? If it is or it’s found by others to be buggy then that would be a blocker.
I would not support converting old threads retroactively. Im fine with the example of course, just it could be misleading because sometimes people reply to people without tagging then as a reply. And it’s just those statements were made in that format so it’s kinda like misrepresenting them.
At the same time it could be confusing for old posts to be different.