Of course it is unnatural and exagerated. It’s the view as a super giant would see it, with eyes meters/yards apart. Or it is a small model world. So much for naturalism.
But then, what’s the sense of making 3D-looking pictures if most of it appears as 2D anyway? This is what 3D photographers talk about. With the distance between the eyes of an adult human, 3D stops at around 15 to 20 m (or yards). Then, the clues for 3 dimensionality come from haze which brightens the shadows, perspective and such. Natural looking 3D landscapes are limited to a foreground of some objects with the grandiose mountain background appearing like a flat picture.
There is nothing wrong with exaggerated “3D-ishness”. There is no obligation to make every render look as perceived by the human eye or a camera. But beware, if you cheat with your scene setup, an anaglyph will show it. I like this example very much. The landscape is built up correctly, it looks spectacular and the 3D effect is profound.