Interference
Destroyer of Words
I'm hoping there are more imaginitive people out there than me
Don't worry, Tansy. We're here
Sounds to me like you over-thunk it. SciFi at its best is about today taken to its presumed logical conclusion. Clones and Robots sit beside you on the train and on the bus, with just the minor distinction that they are born of woman and not through lab techniques. Aliens and monsters are aggressors in any culture, any who seem to want to usurp our rights and unseat our powers. Star ships are villages and towns and communities either threatened by or threatening their near and distant neighbours. Language is just how we communicate, and the author communicates with their audience in whatever way their audience is comfortable with. (Sorry, lost count of the prepositions, there, might be one too many ... )
Maybe there's no real significant difference between fantasy and Sci-Fi, I'm nowhere near qualified enough to comment, but surely any novel aspiring to be a Novel is dealing with human issues, whatever the background; with goals and dreams in whichever guise. There can surely be no real difference between a great Civil War romance and a great Space Opera or Wizard Tome.
Regarding the question heading this thread, once we get through the 1950s syndrome, maybe we should get ready to grow weary of the 60s syndrome and any other decade/era you care to throw a dart at. Personally, I've long been weary of the Arthurian Syndrome of most fantasy writing I've ever encountered. Or maybe I'm just missing the point.