In an interview in the new issue of Famitsu, Miyamoto was asked why Nintendo‘s IPs are enjoyed around the world.
Miyamoto replied that the key to a successful game isn’t looking at what’s trending and trying to capitalise on that, but starting with ideas that the developers personally find fun and working around them.
“People have long asked me, ‘why does a mustachioed middle-aged guy like Mario sell so well?’ and I always think, ‘that’s a bit rude, isn’t it?'” Miyamoto joked (via machine translation). “Well, I wonder the same thing myself – why did an older guy like this become a hit? But if you look at it simply, it’s because he was introduced alongside incredibly fun games.
I know about the Donkey Kong thing but that doesn‘t seem related to Miyamoto‘s claim at all. That‘s just a work story. There‘s nothing about actual life in there.
And yes Star Fox was designed after a shrine spirit near Nintendo headquarters, making him much more of a „real life anecdote“ than Mario or Donkey Kong.