Some are pretty "darn" remote.
The first tracks I found were not "far" from a trail but they were across a deep, swift river in a section very unlikely to cross without a boat. Since they were fresh, definitely less than 4 hours old, and there were no boats other than me in the area, that's practically impossible. Not absolutely impossible but vanishingly unlikely. Other tracks I've found in places where I subsequently set up trail cameras, often quite a few, and in a period of over 4 years I got NO humans on camera in those places. This means if someone was ever there, they never came back. In other areas not so far from those spots I did indeed get pictures of people on camera, rare, maybe 1 (or if 2, they were together) every couple years, so that confirms that I'm setting up the cameras right to catch glimpses of any humans passing by.
All in all, I think the better question is with so little human traffic, how much more evidence is available to be seen that nobody ever does see?