One would never know what story to "prebunk" debunk unless there really was a story to debunk.
The possibilities are endless. One can only prebunk if there is a reason to keep a certian piece of information out of the public arena.
This is the same as developing a "vaccine" for a virus that has not yet emerged. There are limitless types of mutations that could possibly emerge but a vaccine is developed for a particular mutation that has not happened yet and BOOM it coincidentally happens. Amazing.