“The thing that impressed me most about visiting GC is that there are miles of canyon with NO fences, signs, or whatever.”
On the south side there are plenty of signs warning of the dangers, including the terrain, heat, and need for appropriate clothing, hydration, and fitness, and yet I’ve seen dumb-ass people ignore the warning signs and venture into the Canyon. I’ve seen fat people about 100 yards in who realize they are in over their heads and can’t go any further and can’t walk out on their own. And I’ve seen women walking to the Canyon wearing fashion sandals and open toe shoes. The dumbest of the dumb seem to be Asian women taking selfies while dressed as if they are going to a nightclub.
Back around 1974, California was in one of its periodic droughts. In January, we had an unseasonable warm spell and I left before dawn on a hike to the top of Yosemite Falls (which was a trickle that year). I got to the top and had the entire place to myself. Knowing how the mountains can turn on you, I was prepared with the right clothes for sudden bad weather even though it was hitting 70 that day. On the way down, I saw the people you are talking about. Hiking to the top of a high Sierras mountain in January with nothing on them but shorts, t-shirts and sandals. No food, no water, no preparedness for anything
You see that sort all over the land. It is amazing that more of them don’t die.