This is a nice story, but reading on it seems like you're saying that the way app switching works on Windows as the Obvious and Correct thing to do, and that the Macintosh way of doing things is nothing more than a choice that was made too long ago to change.
Honestly, that's absurd.
The Macintosh has a menu bar at the top of the screen which belongs to the foreground application. This is a reasonable place to put a menu bar, because it is easy to click on things which are at the edge or (better yet) corner of the screen. This is a perfectly reasonable justification for having a foreground application.
Windows places the menu bar inside each window. So there is no need for "foreground application", only foreground window.
That's all that you need in terms of explanation. The Mac puts its menu bar at the top of the screen, Windows puts it inside each window. There's no need to tell some story about how the Macintosh was created during a more primitive era of computing history, because that story has no explanatory power.