As Roderick Nash pointed out in his book Wilderness and the American Mind many years ago, we are loving it to death.
Happened to the Appalachian Trail. When I did a trip on part of the trail back around 1970, there was lots of solitude as you ran into very few people on the trail. When I was there about a decade ago, the trail was crowded. same in other places I have backpacked.
Happened to rafting the Grand Canyon. Before 1966, 2,097 people rafted the Canyon. In 1967, 2,099 people did but that was nothing compared to the 16,432 in 1972. Today, trips are regulated, but that also means commercial trips dominate and getting a permit for a private trip is a long, long wait. Appreciation of the outdoors has increased, but with that comes too many people. (I don’t raft.)
Unfortunately, for a lot of people, the wilderness is just part of their bucket list, something to consume and check off. Have an old friend who is a climber. He started in the 60s and is a bit of a local legend with a long list of FAs. Part of his legend is the number of times he has quit climbing in disgust with other climbers who have no respect for rock and treat everything as something to be conquered and checked off their bucket list.
population of the US has almost doubled in my lifetime and is still growing. Just too many people for the solitude we used to have.
of course, I am part of the problem. As more people push into areas that I appreciated in the past, I push into new areas, starting the cycle again.