Millions of people have stood right where AA did when taking some of his most famous shots, like at the big overlook turnout
just after the tunnel entering Yosemite Valley - the kind of tour bus trampled location I dread and avoid. Plenty of other spots in Yosemite Valley are perfectly obvious. Makes no difference. The seasons and lighting conditions are always changing; and millions of other people for some genetic reason just don't happen to be AA. Thank goodness he didn't own a cell phone!
I lived fairly close to there, but have taken only a quite limited number of shots in Yosemite Valley itself. There is another Yosemite, where one can walk for a week with the distinct possibility of encountering no one else.
Many of AA's highway locations are easily identified too. It's just that a lot of things might have changed since then, like the intrusion of development and clutter.
But I was referring more to accidentally stumbling into some his tripod locations in the high country, where it takes some real effort to get to. Same issues - the scenes and their lighting are constantly changing. And who wants another damn postcard image anyway? I don't get any thrill knowing he was once there. What gives me a much greater thrill is finding an obsidian dart point left behind on some remote high pass 12,000 years before Ansel was ever born. In other words, there's more to being a "pioneer" than what exists in modern public records.
I used to get in some heated arguments with another backcountry enthusiast who claimed he was the person who invented trail running. Heck, I explained to him, the person who invented trail running was being chased by a cave bear back in the Ice Ages.