Yeah there was some back and forth about this on Facebook a few weeks ago. It's super sad.
Makes me happy that I was able to see it and appreciate it before it was removed, but makes me sad that I won't get to take my boy out there to see it one day, and will just have to tell him "stories" about it instead.
These environmental organizations that snatch up land are kind of a joke. There is a local one out here in Riverside County called the Riverside County Open Space Preserve District. They operate as a non-profit, but use government money (usually grants, but sometimes it is from private donations) to purchase land and close off (or severely limit) public access to it. Organizations like the MDLT have their own agenda, which is to preserve only NATURAL resources, and human history is not really a "thing" to them unless it's more than a few hundred years old. They don't like things like roads, or trails, or cabins. This happened about a decade ago in Death Valley National Park, when a senior official was orchestrating the removal and clean-up of historic airplane crash sites because he considered them "litter" within the park. It was even proven that he was lurking around on forums for clubs that would go find these sites and catalog/document them, so that he could find where they were and go "clean them up."
I can appreciate their conservation efforts, and I agree that we need people looking out for knuckleheads that tear up the land and the environment. But erasing history is just wrong.