The wind noise from side view mirrors are not unique to the Palisade. For years cars like BMW, Toyota, Nisson, Ford, just to name a few.
Have had problems with mirror wind noise. In large part due to their trying to make the cars more fuel efficient. They have streamlined the shape of the mirror to reduce drag. That may be part of the problem with our Palisade mirrors.
Years ago engineers put indented rows of dimples along the sides and bottoms of mirrors. Some put rows of material protruding in rows along the mirrors. This wasn't always just for show, it was to breakup the flow of the air so as not to cause noise.
Mirrors that fold in haven't helped with whistling sounds caused by the openings where they fold, but I'm not getting the wind noise so haven't really experimented yet.