I am, like you used to work with FF DSLR cameras which all have 3:2 aspect ratio sensor. But I have options to put on my FF 17mm lens or 24 or 50 or whatever. From ultrawide angle to tele if I want. My point with this
M4P 3:2 sensor is that with 4:3 ratio I'd have choice which area to crop to get to 3:2 if that is what I want as my output format. I can keep all the bottom part and only crop the top or keep all the top and crop from bottom. And then there are situations when I want the more squarish format when the subject requires it and that is when 4:3 comes handy and I can use the full realestate of the sensor without cropping.
What I am saying is that the 28mm lens has naturally narrower angle of view compared to 24mm and now with the smaller 3:2 sensor the vertical coverage has been cut to about half. When shooting mostly architecture this makes a massive difference! And all of this without any mention in the spec sheet!!
That is the point I was trying to convey.