Why ban wolf 3D just as they app store does not like the content?
That depends on whether they banned Id's parent company Zenimax from posting it or whether they banned third parties from posting it.
- Third parties, game assets included
- Zenimax has sent notices of claimed infringement to those hosting source ports bundled with game asset files (such as WAD or PAK).
- Third parties, game assets not included
- App store operators want all source ports distributed to the public to be "self-contained", with the engine and game assets in one package authorized by the game assets' copyright owner. A source port with an "Open WAD..." command executes code that has been downloaded from somewhere.
- The App Store Review Guidelines appear to contain what amounts to a general policy against historical fiction. The guidelines as of this writing state: "'Enemies' within the context of a game cannot solely target a specific race, culture, real government, corporation, or any other real entity." NSDAP-controlled Germany was a "real government". Like the adult case, this isn't quite as technically defensible.
Why ban NES EMU's just because big N said to?
Different repositories have different excuses.
- Tom Callaway explained on Fedora's legal mailing list (part 1; part 2) that Red Hat lacks the spare change to pay lawyers to defend a lawsuit. Even if it's winnable, Red Hat's financial resources are better spent elsewhere.
- A ban on emulators probably has little to do with threats from Nintendo. In fact, Nintendo has approved classics compilations containing the free PocketNES emulator for sale on Game Boy Advance (one containing games by Atlus and another with games by Jaleco) and Nintendo DS (extras in Konami's Contra 4). The issue here is the "Open ROM..." command. App store operators want all emulators distributed to the public to be "self-contained", with the emulator and ROM in one package authorized by the ROM's copyright owner. An emulator with an "Open ROM..." command executes code that has been downloaded from somewhere.