Nope. Nothing to do with the intent of the devices. Apple does not and has never made a keyboard for the iPad mini. Why? Because it feels the keyboard would be too small. If it had "chopped" off the top and bottom bezels on the "bezel-less" redesign in 2018 the 10.5"—now 11"— iPad would have been between the OG iPad and iPad mini in size. Too small by Apple's standards for a full keyboard.
So the 12.9" iPad lost it's forehead and chin while the 10.5" iPad 'grew' to 11" and lost the standard aspect ratio.
I think it’s as simple as this. If it wasn’t for concern over adequate keyboard size (in conjunction with portable overall size), I believe Apple would have kept the 11” aspect ratio consistent with every other iPad at 4:3, and probably would have actually kept it at 10.5” like they kept the 12.9” at 12.9” after the bezel reduction.
edit- In other words, when thinning out the thicker top/bottom bezels of the 10.5” ipp, Apple had three choices:
- stay with 10.5” and 4:3, but have a cramped keyboard experience,
- stay with 4:3 and adequate keyboard experience, but have to grow iPad to maybe 11.5” or 12” (maybe someone can do the math there),
- or stay with adequate keyboard experience, and change the screen dimensions as minimally as possible, resulting in 11” at 1.43:1.
For a decent typing experience on a mid-range portability iPad, Apple had to go with the third option.