I tend to think a desktop OS is somewhat wasted once you get down to ~13" or smaller displays, certainly your ability to juggle more than one window on screen at a time becomes more limited. I think there's only so far super dense resolutions or software tricks like Stage Manager can go to make up for a lack of physical space. I'm sure there will be those who will say they use their 12" MacBook just fine, but I think I'd really struggle, which is why the iOS model which is built around one app at a time, with some flexibility to split screen or slideover is ideal for 10-13" tablets. On the flip side, maybe if Apple's 14/16" "iPads" became reality, Stage Manager would come into its own more, but I also think that would stretch the iPad paradigm to the limit so these would more ideally be a new product line ("iBook"?) focusing on docked usage in my estimation.