Surfaces (Pro and standard) have been 3:2 for a couple years: https://en.wikipedia.org/wiki/Surface_3

Not refuting your implication necessarily, but worth knowing their flagship (standard and high-end) devices have been 3:2.

I see where you're coming from, but those aren't large screen devices.

Most games and movies are widescreen these days, and I see those as consumery activities. I think a significant amount of consumers would be annoyed by letterboxing in those use cases.