Don't really know what this means without playing the game though? I doubt it means it becomes like FFXIII. Could still mean it has open environments, but has a greater focus on following the main missions. Which is actually kind of what he says at the end. "Chose to follow the main route" seems to imply to me that there's still other stuff to do in the 2nd half.
Either way, I hope his game is like Xenoblade. Big environments, but still a linear main mission.
I don't mind, because at the end of the day I'm not such a big open world fan and prefer more focused games.