> I'd like to state that I sure wouldn't mind seeing officially supported fully open > versions of Mame/Mess on places like Steam, Google Play, iOS (do they allow emulators > at all?).
Steam does. Several games there use DOSBox (Wolfenstein 3D, Commander Keen, some older Sierra adventure games, and so on), The Bard's Tale has the classic Apple II versions built in, and Sega has a crappy Genesis emulator (no, seriously. It's got awful video and audio support) to play games you buy in Steam. Which are also encrypted and can't be used on other emulators.
Steam would probably block it because they're jerks, though.