However, if you are off trail, and in fact doing so at a pretty extreme level like Larry, how is a tracking device supposed to help you? Are we to assume he was in some way incapacitated, but otherwise could have sounded an alarm if so equipped?
So I'm not sure what's not getting across about search and rescue here. Larry's is probably a good one to use as an example. After he talked to someone at the trailhead and gave a couple of ideas of where he might go, he utterly vanished. There was not a single clue or foot print found during the entire search -- about 50 ground searchers and up to 3 helicopters with thousands of hours of cumulative search time. Not one clue. It goes without saying there was a huge emotional toll on those here, his family and the searchers.
It is clues which concentrate the search. They can be physical (a track or camp) or discovered by investigation (interviewing the last person to see him). Tracking devices have the potential to add one more clue: the person's actual location at a certain time. True, if they're only checking in, say, twice a day, you've still got a big area, but you've also got a smaller one than what you would otherwise have without a clue (so to speak...).
Most everyone here knows how huge the search area for Larry was. It matched almost exactly that of Morgenson in '96. No clues there either. So the only point I'm making here is that these things can significantly reduce the search area or even pinpoint the location exactly. That is a huge, huge advantage on a search or a rescue (not the same thing, of course).
So, it appears that Heng, Dankworth and Ybarra all died instantly. But all involved multi-day searches of fairly large areas in extremely dangerous terrain (after all, these guys died there, so now you're sending more people into it...). In answer to your question, then, a location signal would have been a darned good thing to have. Again, it would have reduced risk to the responders and brought quicker resolution to the families and friends.
Next: being incapacitated and unable to push the button. Not sure where this is coming from either. Even if the person is dead, you still have a tracking location reducing the search area -- a major reduction of risk for searchers and consolation to the family if the person is thereby found more quickly.
But the majority -- by a huge margin -- of searches are for people with survivable injuries or who are actually lost who CAN push the button and call for help (as well, of course, as some bogus calls).
And, absolutely, those of you against them can cheerfully accept possibly dying as a risk. But there's no question you're also then accepting the risk of anyone who comes looking for you. I'm not necessarily against that, but strongly pointing out that it's not just about you. There are other considerations to be weighed.
I've never gotten to an injured person and had them say, "no, don't rescue me, I accepted the risk, I'll just die here" (or get better..).
g.