Hasn't there always been a difference between the music in the 3D Zeldas and the 2D Zeldas? At a quick glance right now, nearly all the titles in the 2D titles (including the 2D ones) are far higher pitched than the 3D Zeldas.
I would say that this isn't a radical change at all. Essentially, what this might be is
In the original titles, the music was higher pitched and rather hectic.
Then OoT comes and it turns into 3D, with lower pitched music that's less hectic. It plays a less important role, actually.
And now this is more of a continuation and development of the 2D style again. It's the logical continuation, isn't it?







