Dark Souls is different from Zelda, in philosophy and design.
It is your own tastes that makes you like Dark Souls over Zelda as of late. It is not an end all be all "Dark Souls is better than Zelda", because, as Miyazaki said, they both cater to two different audiences and 2 different philosophies in design.
Dark Souls doesn't have the charm, the inuitive level design, the quality of puzzles, the focus on amazing items, the character designs, nor amazing music that the Zelda series has.
Zelda doesn't have the difficulty, the danger of enemies, the traps that make you plan your movement, the engaging and deep combat, and high skill ceiling that Dark Souls has.
That's okay for both of these games, as they set out to accomplish two different things and reach different audiences.
Zelda should never have the difficulty of Dark Souls, because it is extremely unintuitive whilst paired with the focus on puzzles and exploration. Dark Souls should never have the progression of a Zelda game, and shouldn't have the focus on puzzles and exploration, because it focuses on combat.
If you prefer Dark Souls over Zelda, that's fine. Dark Souls is more catered to you. But you cannot compare two different series that cater to two different philosophies. It's like saying the Xenoblade Chronicles is a better Skyrim. They are both RPGs that focus a lot on huge big worlds, with excellent world building. But they both cater to completely different audiences, and are way to different to be compared to.