Most things that you can imagine have been the subject of sci-fi or fantasy at some point. There is certainly a large fashion element in the decision what to make the next film about and it is fun trying to spot what will come next.
Witches went out of fashion a decade ago even while other sword and sorcery, dungeons and dragons stuff remained stable and recurrent, albeit a niche. Vampires and werewolves accounted for far too many films and became boring, though admittedly, some of them were very good fun, so it’s safe to bury them for a decade or hopefully two.
Zombies are among the current leaders, (as I predicted several years ago, in spite of being laughed at back then). It is still hard to find a computer game that doesn’t have some sort of zombies in it, so they have a good while to go yet. The zombie apocalypse is scientifically and technologically feasible (see https://timeguide.wordpress.com/2012/02/14/zombies-are-coming/) and that makes them far more disturbing than vampires and dragons, though the parasites in Alien are arguably even scarier.
Star Trek and the Terminator series introduced us to shape shifters. Avatar and Star Trek enthused over futuristic Indians. Symbionts and proxies are interesting but that’s really quite a shallow seam, there is really only one idea and it’s been used already. Religion and New Age trash has generally polluted throughout sci-fi and fantasy, but people are getting tired of it – American Indians and Australian Aborigines have been apologised to now. Recent Muslim backlash however suggests that the days are numbered for Star Wars, Dune, Mk 1 Klingons and others tapping into middle eastern stereotypes, so maybe that will force other exotic cultures into the sci-fi limelight. The Cold War has already been done in overdose. South America has already been fully mined too. It’s a good while since the Chinese and Japanese cultures had a decent turn and I suspect they will come back strongly soon, whereas Africa doesn’t hold enough cultural identification points yet. Homophilia is having recurrent effects from Star Wars to Dr Who, but apart from gender-hopping, there isn’t really very far it can go. You can’t make many films from it.
So if those are the areas that are already showing signs of exhaustion what comes after zombies? Gay zombies? Chinese zombies? Virtual zombies? Time travel zombies? Yeah, but after that?
Here’s my guess. Clouds.
Clouds are the IT Zeitgeist. They are the mid term future for sci-fi. There are a few possible manifestations and some tap well into other things we are getting to like. Clouds are a deep seam too. Not just one idea there. We have self-organisation, distribution, virtualisation, hybridisation, miniaturisation, self-replication, adaptation and evolution. We have AI, biomimetics, symbiosis, parasitic and commensalistic relationships. We have new kinds of gender, new kinds of intelligence, new physical and electronic forms. We have new kinds of materials, new ways of reproduction, new forms of attack and defense. I could write dozens of sci-fi books based on clouds. So could other people, and some of them will. Books, games, films, lots of them. About clouds.
You heard it here first. Clouds are the future of sci-fi.