I'd always heard they never said what it was about

Musicians tend to dislike talking about the meaning of their own songs, preferring the listener to make their own interpretation. It's part of all art: The viewer/listener adds themselves to the experience, making it more than just what the artist created. But for what it's worth, "Hollywood in the 70's" was a specific quote I read from Henley himself (long after working it out on my own).

Oh, and there's a more recent one Henley did about Hollywood in the 90's, called "Garden of Allah". Love that one. Always considered it a sequel.