Why not use the delay mechanic?
Because the creature would still be in play. The idea behind this card is that it is going forward in time, like an opposite to Rewind. Plus, the delay could be broken in a number of ways before the three turns was done.
Additionally, this card also meant to be used as more than a delaying mechanism. For example, lets say you have a creature with high atk, but low hp. Your opponent plays an Oty and you have no immediate way to deal with it. Use future vision on your card to protect it for those three turns or on the oty to delay it devouring your creature. Or maybe your opponent has a creature with gravity pull; use Future Vision to get a few turns to damage your opponent.