As for why the MD gets credit? Probably because The Guardian couldn't decide on whether they wanted a wholly subjective "best of"-list, or a list based on impact and influence.
Yep. I loved my SNES when I was a kid, but it really didn't do much apart from being an improved NES. Same feeling about the PS2 - I love it, but nothing really changed from the PS1. The Switch is more interesting than either, since it actually changes how Nintendo does business.