I came up with a theory about the development of why XY was so small. I think that Nintendo was originally going to release Gen V on the 3DS using the XY graphics engine, but something happened that pushed back the release date. To pad time, they decided to implement the new Poke designs. For instance, you can see statues of the Tao dragons in the garden (scrapped from the original draft of the game?) Plus Team Plasma’s knight-getup would make more sense if they lived in a European-type region.