It is is hard to say really, it is possible but truthfully, a team's first effort with a device RARELY ever does push the system.
Xenoblade Chronicles X, seems like it could be but who knows if Monolith Soft had to do another game if they could get more out of it. It is also hard to judge any Nintendo system by their main internal studios as those teams rarely go out of their way to force their system and indie studios usually work on a smaller and tighter budget meaning they also aren't likely putting extreme tax on the system.
So what I am saying, similar to how we never got to see the full capability of the GC or even the original Xbox for the most part due to developer effort and focus on the top system, the PS2 which was weaker internally, I doubt we will ever see the full limits of the Wii U mainly because no one will put the effort into trying to reach them.







