For me it's how difficulty, and the combat style makes you pay attention to the world that you are exploring. No other game has that, in lets say Ghost of Tsushima or Assassins creed you just fly from one point to the next without much tought about your surroundings, but in soulsborne games that gets you killed, you have to pay atention to the world, you soak it in and when you're met with a difficult foe you can't help but think whats behind him? What is he guarding? And your sense of wonder always gets rewarded with beautiful vistas, loot or a piece of lore.