Maybe because I'm from France and you from the USA? ?
I use the Webcomic format a lot, which is something around "3:2" :
https://makingcomics.spiltink.org/pgtemplates/
A4 format is mostly used here, but for Comix, BD and manga, different book aspect ratios are used. Actually, I don't know the exact values myself.
PS : When I used the Surface, I was satisfied with the image (the tiny black top and bottom lines were completely negligible) , but as you write, the only thing that limited me a little (nothing bad) was the weight and therefore the comfort when reading.