For me, grouping by app is terrible. Yes, they may all be "Terminal" or "Firefox" windows, but they are for very different things. I'd rather see things grouped by project regardless of "app". But that is what tagging window managers are for :) .
Given that macOS forces that (IMO) braindead tunnel vision paradigm, I think the response should be "Wù".
For example, because the app restores its state and you have a few "projects" within the app.
> I'd rather see things grouped by project
Ok, and what if that project is encapsulated in an app window? Why introduce an extra level of indirection for no reason and spend time configuring it? If you frequently need a set of "5 firefox tabs, 2 terminal tabs, 4 text editor tabs, each in a separate app window", sure, spend time tagging it, set it as a WM project and launch/activate it with a key, but not everything is like that.
I'm saying that given what details are there, I think the author is closer to "my" end of the spectrum than one where the question makes sense at all.
Ok, how does that address my initial question (which was not about you) then? Not everyone's setup is so primitive as to only be centered around two apps
Though in this case I don't get what is so terrible about app groups if you don't group anything else anyway since it's ephemereal, so wouldn't any grouping work (except for 2 apps)?