> What’s wrong with cmd tab and just switching between apps?

Open 3 terminal windows. Try to switch back & forth between just two of them with a keyboard shortcut (without mentally tracking whether or not to press Shift). You can't.

Open a browser and two terminal windows. Try to switch between one terminal (your editor) and the browser window (your reference docs), without also bringing the other terminal above the browser window, covering up your docs. You can't.

> Is this going to be some Kind of major epiphany?!

If you don't use several windows per app, probably not. But, I do, and macOS's window manager is awful for it.