Yet Another Harry Potter Prediction

Not so much a real prediction, but more of a possibility for a way that Harry Potter and the Deathly Hallows (Book 7) could end, although low on my list (I would say the Harry is/was a Squib before being made into an accidental Horcrux theory of mine has a better potability than this one.)
What if the Department of Mysteries, and the Unspeakables who who work there (Harry’s mom may have been among them) were guarding the secret to magic itself? What if the only real way to get rid of Voldemort is to get rid of magic? This certainly would make Joe’s idea true that it would be hard to write more for the series afterwards. It may go one further and remove magic from before everything started… of course that would leave bigger questions in that case, such as would people killed in the magical world then be alive since the magical world never existed? Because of that, I would say the more likely way to go is that magic would be removed from the world from that point forward. What that means for magical creatures is another issue.
Admittedly, this is probably a slim chance prediction, but I put it out there just in case I am right, I can say “See, I told you so!”