Fiction and the fantastic

Fiction should be fantastical. The entire reason fiction exists is because it can contain and express human-created concepts that have no real-world analogue. If you are writing fiction and you are constraining yourself within the set of things that are real and actual and possible, you are wasting your time and your audience's time as well. You want a story about the horrors of war, or the tragedy of drug addiction, or the quiet malaise of 1950s suburbs? They're out there already. That ground is well-covered by actual people and the actual experiences of their actual lives.

But robots and vampires and aliens and time travelers and superheroes and zombies and talking gorillas? None of that is real, or at least not yet.