It would be great if it would interface the disk drive to the cores, but this is not loading the game from a disk but using the disk drive to tell the MiSTer which core and game to start from its regular storage.
What is next? Starting a game with a rotary phone? In the end it is again and again the same tapto gimmick, with another device emulating the NFC reader.
Well yes, yes they did. It is called Canoe and is for example running inside the SNES Classic Mini. And that is not the only emulator they wrote. Writing an emulator is not some obscure magic, and it is way easier if you own all the schematics and other Information used to build the original hardware.