Though it does have a terrific score, the book is very skeletal. I think that the original didn't get great reviews either in London or on Broadway, but managed to be moderately successful because of the performances, the songs, and interest in its unconventional nature. And because it cost so little to produce and run.
Another reason why it might not hold up too well in revival is that so much of it is satire that is no longer applicable. Younger people might be truly lost during some of it.
Again, I like the score a lot. I just think it was very much of its time.