https://en.wikipedia.org/wiki/List_of_Super_NES_enhancement_...
Many SNES games include one-off chipsets that common SNES emulators implement as well; for example just something simple like saving your game can't be done on an SNES and needs an expansion chip.
If you were to write a SNES emulator that only emulated the console itself, it would not be able to run the many SNES games that use addon chips. SNES emulators include code that emulate the addon chips originally contained in the cartridges[1].
So, I think your test is a false one. Games run in the emulator because the emulator added emulation for the chips in the game. This game cartridge would also run on a SNES emulator if you emulated its chips.
[1] Code to emulate the behavior of the DSP chip in Super Mario Kart (among many others): https://github.com/bsnes-emu/bsnes/tree/master/bsnes/sfc/dsp
You couldn't download this demo into a ROM image and run it on an emulator. To make it run, you'd have to beg the author of the emulator to actually support your chip.
This is more than a silly, pedantic distinction; emulators are probably the way that >95% of the current SNES playerbase runs the software, and they're likely to remain that way … forever? I don't see the interest in running SNES games ever really going away, since they're fun in a timeless way (like classic books/film), so emulators that support it are likely to stick around for several centuries, barring civilizational collapse. Actual hardware's pretty close to dying out (the recent "SNES Classic" physical devices, afaik, are just neatly packaged emulators).
So I think it really does matter whether it runs in an emulator or not.
(Not to diminish the fairly awesome technical prowess of this hack)