Earlier quoted context omitted.
The same thing could be said of game streaming apps like Stadia (all the game code is running remotely) but are forbidden in the App Store. It's hard to take Apple seriously when they do shit like this.
They aren’t forbidden anymore. [1] It is weird they’re making it so that each game you’ve bought needs a separate App Store entry, especially since the local code is all the same and a thin shim. That being said, the same rules are in effect for Apple’s own game platform so maybe there’s a specific reason (eg uniform experience for any app, they can properly promote individual titles in the App Store instead of allow…
Having each game as its own app means each game gets its own app-store age rating; its own star-rating, reviews, and install metrics; its own parental-control settings (e.g. screen time limits); its own corporate MDM blacklist-ability; and the ability for Apple to block that individual game from being installable, either temporarily because it’s breaking App Store policy, or permanently within some country whose regime doesn’t allow it.
Also, Apple haven’t mentioned exactly how they’re implementing this just yet, but I would guess that the game streaming services are going to be required to have each client version paired 1:1 with a particular release of the streamed game, such that you must update the app to connect to an updated streaming backend. This would put Apple’s App Store review team back in the critical path for approving changes in app content.