Regarding Yosemite... Actually, Yosemite people acted without much input from Inyo, too. At least that was the information I was given. Once the process blew wide open with lots of hikers and people giving input, they may have worked with Inyo.
But I think YNP tried to solve the problem from their end, which will result in more JMT hikers hiking northbound, or hiking from Reds/Agnew meadows INto Yosemite, then taking the YARTS shuttle back to Mammoth, and hiking south. Inyo even had a term for this: Just more "hikers on the bus".
Regardless of who is making new rules for whatever reason, my own personal opinion is that hikers are foolish to wish for a "wilderness experience" where solitude is a big part of their definition. There are SO MANY ways to find that wilderness solitude, but they should NOT try or expect to find it on the most heavily traveled trail in the Sierra.
