It's interesting in that if someone says "yeah but there's not enough to discover" I can sorta see that angle, if there's one flaw in BotW's world it's that it's perhaps too big in regards to a ton of mountainous landscapes that feel a bit less involved than half of the game's map.
Yet similarly to the forbidden land in shadow of the colossus, those areas of vast emptiness are what help create this sense of place, it's not "empty" in a traditional sense, it's like room to breath (breathe in the breath of the wild as Kass would say), a sort of calculated vastness that accentuates what a world is actually like and in turn makes those more populated areas stand out that much more.
Of course it's not the only open world with a large countryside peppered with a few populated areas, not by a long shot, but then that's where the triangle rule and Disney design doodad already mentioned come into play and create something that runs with this angle, with visually distinct vistas and alluring monuments. Combine that with the freeform climbing and the unparalleled immediate openess/freedom of the map then you have one hell of a stew brewing.
I don't really want to play that ol' comparison game here but really I just can't help but think that when I played Horizon afterwards, that the map felt like a bunch of area chunks slammed together in a manner that had no flow.
While I'm not fond of the gameplay of Bethesda's open world outings, Hyrule manages that similar tug at one's curiosity where you had a plan to head to point A but got sidetracked into a good chunk of detours en route, which isn't bad for a game that isn't going to lead you to some rip roaring sidequest chain (because let's face it, if BotW does one thing in a mediocre open world way, it's sidequests).
I've gotta say though, among some criticisms there's one that strikes me as 100% maximum "wut?" and that's discounting the discovery of shrines, outside of the chance you'll get one of the guardian combat shrines that make up a small number of the overall total, that's the discovery of another unique puzzle chamber or unique overworld riddle presented via bard bird, the very essence of Zelda's core and how the dungeon dynamic of past games truly lives on moreso than any of the divine beasts.
At this point I invoke the
Forkball post from earlier and direct you to Dr Evil.