If you have projects that fit within an app, sure. I do not. The only "apps" seen on my machines are terminal windows hosting tmux processes and Firefox. Everything else is ephemeral (mpv, dialogs, rofi, dunst). App-centric behavior is just the wrong axis for this setup.
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)?
The Sapir-Whorf is strong in this thread. MacOS' app-centric model makes it hard to even imagine other people's workflows. Stop thinking in apps, think about a task. I have multiple tasks (workspaces). Each task has multiple aspects (windows). Apps are a distraction, an accidental complexity. I want to switch between tasks and then subparts of those tasks.
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.