Well. That is quite something and I never would have expected it. However, 'cause my predictions have been so good (note: subtle use of irony...), I'll say it's really unlikely packers will lose their season. I have absolutely no special knowledge here. But it sounds like the two sides (NPS and HSHA) are playing chicken. Presumably there was an attempt to come up with a compromise that agreed with the court's finding (that NPS was in violation) and that neither side blinked. The judge, then, will impose a compromise.
Who is it that decides what is natural and what is wilderness? Trails doent seem very natural to me. Either do tents. Muir Hut is anything but natural, and its right in the middle of the wilderness. Should it be removed???? How about signs, bear lockers, summer Ranger Stations?
All excellent questions, of course. As Don Rumsfeld might have put it, you manage a wilderness area with the terrain you're given, not what you want. So everything inside whatever arbitrary boundary when the wilderness is designated is what the wilderness is. Ipso facto. Or something like that.
All that stuff you mention was already inside the boundaries of those places when the Wilderness Act was applied to, say, Sequoia Kings & Yosemite: trails (1860s +), ranger stations (most from 1950+; some back to 1890), Muir Hut (1930 or so).
Other stuff is found acceptable if it furthers wilderness values. A darned squishy concept. But bear boxes might be a good example. Bears get food from people. Is it more important to prevent that -- to preserve the wildness of bears -- or to allow a steel box in certain areas which is aesthetically objectionable but keeps bears wild?
Ranger Stations. Same thing. Does the presence of a ranger station and ranger contribute to preserving wilderness character? Rangers educate visitors on the importance of minimum impact, pick up garbage, take apart fire rings, monitor resource damage and work to mitigate it, take care of sick and injured etc. Is there likely to be more short & long-term impact to wilderness if the ranger can't be there as much or at all? So does that balance the intrusion of a ranger station?
The answers are not easy or obvious.
The Wilderness Act has forced agencies to think and act more critically when faced with different choices. As a result, it's unlikely any new trails will be built; or that another Muir Hut will be built. Incidentally, tearing that down has occasionally been mentioned -- though never really seriously. In that case, there's two opposing regulations: Wilderness Act, which might argue to tear it down (though not necessarily) and the National Historic Preservation Act, which would preserve it. Same with the hut on Whitney. When the boundary lines for Yosemite Wilderness were drawn, Ostrander Hut was specifically excluded (just a side note).
So this case was brought because HSHA did not think that NPS was thinking carefully or critically about how they regulated stock in Wilderness. A federal judge agreed (as have 3 other federal judges in similar cases over the last 10 years). So here, anyway, that's who decides. Kind of a dismal way to run a park or wilderness but, I have to say, compromise was possible decades ago and this whole thing could have been avoided.