青沼の海外インタビュー記事ではこのような発言

In a recent interview with Gamekult, Aonuma explained that,
while Monolith assisted with graphics design and other elements in Skyward Sword,
their role in Breath of the Wild was focused on topographic arrangements for the game’s vast open world.

Here’s Aonuma’s full comment about Monolith’s involvement:

“On Skyward Sword, Monolith had mainly helped us on graphics design and other artistic elements.
Even though we could have asked them for help on the technical side,
we realized their way of making games was completely different from ours and
we didn’t have much to learn from them on this installment, since we were almost doing two different jobs.
On the other hand, for Breath of the Wild, we’ve been assisted by level designers used to large game areas,
in order to make topographic arrangements.”