Any supporting research concerning this theory besides Renaissance philosophers or 19th, begin 20th century romantic painters? Le Corbusier based it's modulor on phi, but that only applies to humans. I understand that people in paintings and statues with phi correct proportions will appear more aesthetically (might be evolutionary), but why would things like displays look nicer with golden ratio proportions?
If you google research concerning the golden ratio, you will find some. The genetically based preference for the golden ratio is suggested because it is found throughout nature and is cross-culturally preferred.
The information I provided only applies to objects within a composition; as far as I know it does not apply to the perimeter of the composition so it therefore most likely does not apply to the aspect ratio of a display.
A lot of art and natural structures (flowers) do not have the golden ratio defining the borders yet have a good aestethic quality due to having the golden ratio within those borders.
From what I understand, people actually prefer wider aspect ratios because these displays better fit our visual field. I believe this is what is driving the move to 16:9.
Maybe the application of aesthetic preference in regard to the aspect ratio of a display is dependent on whether the observer is looking at the composition of the display itself or the composition of the objects displayed within the perimeter of the display?
Weirdly, I prefer the look of 16:10 laptops but prefer using 16:9 laptops. Whether this is biologically based or not, I don't know. I would speculate and say that this contrast in preference does have some biological foundation.
BTW, the actual perimeter of the iCloud icon is, for the most part, a square.