I am guessing (sadly) that Apple’s understanding of an emulator is as simple as ‘thing that sits between game and player to make it work on system’.
Technicalities aside, ScummVM has that in common with any emulator, and so whatever drove Apple to decide against emulators I imagine would still apply.
I can see a world in which a game and ScummVM are bundled together as an app and sold, similar to what is done on Steam except perhaps a bit more locked down so you can’t run other games on it.
That’d need a publisher though, so unless that’s what this recent Zoom Platform shilling is all about, probably brings us back to Disney.