Science fiction writers take a great risk when they imagine any sort of future: the passage of time may make their overall view seem risible. Sci-Fi movies are especially risky. The audience that sees a movie forty years later will note at once the clunky, old-fashioned technologies that populate future-tech. For example, imagine a world with booths that can transmit people to other planets, space flight, laser pistols, and clunky, 1950s-style telephones.
Frank Herbert is particularly good at imagining his future. In his history of Dune, the “Butlerian Jihad” decreed that no machines would be made in the image of a human mind. By decreeing a future without computers, Herbert freed himself from having to imagine how computers could transform the future. And, in my opinion, he is on solid sci-fi ground when he imagines new technologies in his universe. I will provide you with two very minor “clunkers” to illustrate this point:
(A) Saguaro cactuses grow on the deserts of Arrakis. I believe that in 1965, Herbert was unlikely to know that Saguaro cannot grow without the protection of “nurse trees”, such as mesquite. Saguaro grows up under the protection of a nurse tree, eventually killing it as the cactus grows tall. Nurse trees - decidous, needing more moisture - probably could not grow on Arrakis, and Herbert does not mention anything like them. Therefore, Saguaro could not grow on Arrakis.
(B) The people in Dune wear wristwatches that appear to do nothing but tell time. More amazing, they need to be set by hand to the local time zone!