George Orwell, I find to be quite extreme (maybe sensationalised) story. However Aldus Huxley's and Yevgeny Zamaytin worlds were more realistic in the sense that the population were convinced of the morality and generally happy about their u/dys-topian existence.
I think that they did have the skills, or had access to people who had the skills, to extrapolate what certain trends/policies of their time would produce in the future.