Ahhh, one that I have seen first-hand.
My feelings on this one is that it is as near perfection as a landscape photograph gets. Everything about it is just right. The geometry, the lighting, but especially the lighting. How many of us would try a back-lit shot like this and pull it off so well? It goes against practical convention and is tricky to do, never mind do so well.
I'm like David, I have the Adams Triad on my shelf and still refer to them regularly.
As far as relevancy to the young generation, not too many get out into the wild and appreciate the beauty of our land, in my observations. I have seen that its not fashionable (hence "cool") while Ansel bashing is cool. Not all do this. There are some young APUG members that appreciate Adams and his work. My own kids get perterbed at me because I like to get off the Interstate and see what's on the regular roads. I keep telling them they have no eyes.
Adams fully appreciated what he was photographing.