The USFS can be quite responsive if one approaches them in the right way.
Every Spring, as we locals start using trails, many of us watch for potential trail problems: fallen rocks, trees, erosion, etc. Then those problems are reported, in person, to either the White Mountain visitor center or the visitor center south of Lone Pine, depending on which one is nearest the trail in question. The FS is very good at following up on those reports, and dispatches a trail maintenance crew, as soon as one is available, to fix the trail. This approach seems to work a lot better, and in a more timely manner, than writing letters, signing petitions or making 'phone calls.
Also, the various pack stations on the East side (and probably on the West side) are very good at fixing damaged trails as they begin their packing season. This work is done with the approval of the FS. Every year we see packers working to clear snow on the switch-backs below Bishop Pass; makes it safer for hikers and pack animals. They are very good at this work, and have been doing it for generations.
I would recommend that those who have concerns about the Mt. Whitney trail conditions make an appointment with the Forest Supervisor, and explain the situation as you perceive it.