You know, I don't think that's necessarily true. The reason for the false 9 was of course to increase his influence, since in the traditional 4-3-3 he did get isolated and drop out of the game sometimes. By pressuring the Barca midfield the opposition could reduce the supply line to him. In that sense of course it makes sense not to go back to that.
However, what maybe wasn't considered was that you could play Messi as a winger, or maybe more accurately an inside forward in a false 9 system. In a sense this becomes a 4-4-2 with a diamond in the middle. That means you gain more control in the middle, it also means you can keep a good supply line to Messi. In essence the false 9 plays close to Messi, and pretty much will always get him the ball. However since Messi is now in the front line, he will get the ball in a more advanced position.