Daybreak Town becoming the Keyblade Graveyard (why are we spoilering this? It's just idle speculation) would preclude it from being a playable world in KH3, since that's where Master Xehanort intends to have his clash of Light and Dark take place. Which would be something reserved for the end game, I feel.
For that reason, I would most certainly NOT want that fate for Daybreak Town. Because it'd be a waste. And there's no way to return the town to the way it was ala Radiant Garden and (eventually) Land of Departure (even if it was battered prior to the transformation):
That "world" got REKT. There's no coming back from that. I'd rather the Graveyard be a different location that the factions have to actively seek out, than be right under their noses the whole time.
KH3 needs a hub town.