Miyamoto doesn't really play video games, and it kind of ends up being a double-edged sword. On one hand, he can be slow to pick up on his own mistakes or seeing when other games or companies do things better, and on the other hand, he has a clearer mindset going into making games and isn't too prone to following industry trends. He's more able to see what truly makes the games enjoyable, and still make things fresh even if it still follows the same formula of older games.
I remember Miyazaki saying a similar thing about Japanese animation: the problem with today's anime is most authors are anime fanboys. This makes them get caught up in the tired old tropes and motifs and stops them from doing something truly creative with the medium.
Miyamoto actually hated video games when he started out. The concept of them itself was somewhat annoying to him, and especially the way they were designed. He was making box-art for the games, and the higher-ups liked his work and wanted him on-board to design something fresh out of the arcades they had dumped across the States. AKA, he was essential forced to work on them to save the company, because he was a genius with innovation in general, and didn't care how things were done, so did what he thought was interesting.
Miyazaki (and Ghibli itself) decided to call it quits because of exactly that. Demons, blood, hot girls and ninja swords took all the focus, and all of their latest movies suffered for it. Their last movie, Princess Kaguya, is a movie that I'm pretty sure almost everyone in the world (able to watch movies) isn't even ready to see yet. Touches on such deeply rooted topics everywhere, and never finishes them, leaving it open to interpretation, which can be taken very off-the-mark if the viewer isn't looking at enough layers. We'll be sticking with **** and fights for a bit now.
There's a void opening up in the art world. The general concept of story-telling is still studied in things like terms (Tropes/Formulas/whatever) rather than what an attempt at an expression, and interpretation on the receiving end, can do to the disposition of the mind of both parties. We're far off from understanding what we already know in these kinds of faculties for that reason.