It is fiction, so it isn't a history book and there are plenty of assumptions on how things will work. However, in good fiction, those assumptions are plausible and highlight a future that may happen.
Dismissing fiction is just like having a stock manager that dismisses quarterly reports since they don't definitively tell you how the company will be doing - they just tell you how it has been doing. Prediction and imagination are not flawless tools, but they are helpful to plan for the future. (Which is amusing to say in the light of the book being discussed)