The thing about “See that mountain? You can climb it” is, it was never all that fussed about the actual climbing part. It was just a promise that some conspicuous peak in the distance was real, something you could touch and stand atop, and if the reality of that meant switchback bunny-hopping against a low-res rock texture to no real benefit, well, so be it. If we think of it as a mathematical proposition, it would be much more interested in its own unstated corollary: that if the mountain is tangible, everything on the route between you and it must be tangible, too. And who knows what mysteries that might hold?
This is a companion discussion topic for the original entry at https://www.vice.com/en_us/article/y3dv7m/insurmountable-finally-gives-us-video-game-mountains-worth-climbing