I doubt you'll see this, but I am unsure if the digital version of The Machine can be played online in the same way the demo can be. like, can I play the digital version on a MacOS?
You can play it on MacOS using a program called an emulator. It pretends to be a Gameboy and runs the rom file. Here is one example of a free Gameboy emulator for MacOS: https://sameboy.github.io/downloads/