The point is that the word 'information content' is misleading outside the mathematical context. The words in a book are carefully selected for their meaning . It should be no surprise that the compressibility definition of Information Content yields such paradoxal results, because compressibility ignores the meaning of the symbols. For a computer, the book would have lower information content. Without label each random string is just a random string and nothing more.
Labels create meaning.
Those random strings could be labeled in many ways. But then there is information in the code table. This type of information must fall outside the original set of random strings. However, what's really important about a message is not the quantity of information, but its quality. Information theory as written down by Shannon is not a theory of information content.