I have developed a crazy theory. It's guaranteed to be at least partly wrong, but there might be an element of truth somewhere in it.
The theory is that the settling of North America ruined The Landscape as an artistic subject. From the point of view of Western European Art and its derivatives.
In the 19th century, and probably before, we have painters painting landscapes. Sometimes with people and buildings, the "hand of man", and sometimes not. These painters were after something about the sublime, about beauty, about the hand of God in nature. Some of them did a darn good job. These paintings required a bit of effort, since all these guys were working in Europe, basically. Since I've already restricted us to Western European Art and its derivative, I get this for free.
Europe is not exactly awash is pristine landscapes. There's plenty of rural scenery, but there are people and so on all over it. There's a lot of farms and towns and cities, and people who build stuff have been rattling around there building stuff for thousands of years.
Now we get to America, and start painting pictures and taking photographs. America is awash in landscapes, in the sublime. The hand of God in nature is available in million square mile lots. You want a sunset over the ocean, with attractive rugged forefround? Sure! We got 3000 miles of that on the Pacific coast! Mountains? What kind? We got big ones and small ones, we got snow-capped and green, we got old ones, we got new ones. We got mountains. Picturesque mountain valleys? Heck yeah! You want one with a log cabin, or not? We got like 1000 with and 2000 without. Vast expanses of grassland? Did you want a sunrise over the ocean instead of a sunset? No problem, other coast, 3000 miles. You want rocks, trees, or sand in the foreground? What about fjords? Islands? Yup.
Now we've got a 100 million pretty decent landscapes on flickr and 500px and instagram.
Now when you see most landscapes you barely see the picture at all. You see the cloud of similar pictures you've seen in the past. You relate to this picture largely in terms of how it resembles and differs from those pictures. The sublime, the beautiful, the hand of God in nature, that's all pretty much lost. It's another one of those pictures.
You can argue that Ansel Adams and f/64 started closing the book on the subject, and Galen Rowell and his acolytes came along and slammed it shut. And nailed it shut, encased it in cement, and bricked that up in an alcove in the basement.
There's probably more to it than just America, but I feel like that's a piece of it.