@lispi314 I do not understand aspect ratios well enough so I do not want to comment too much on that.
What I meant by physical size awareness is that I believe that the fact that your display is a 1920x1920px should be of a secondary importance compared to the fact that it is a 30x30cm display, for instance.
Displays should expose their physical size and then applications should set its UI element sizes by, say, millimeters, and only do the conversion to pixels at the very last moment before painting.
... and after that we could probably get rid of all those display scaling madness :02lurk: