Here’s the problem with either writing sci-fi or (if you’re Margaret Atwood) “speculative fiction.” Often you have to be an expert in technologies, societies, and minutiae that not only don’t exist, but are be ridiculously improbable.
Take space travel. Space travel is ridiculous. It involves literally incomprehensible amounts of space through an environment that is notable for having no environment at all. A lot of empty space is oddly known for being full of things, like lethal amounts of radiation or micro-asteroids. One doesn’t travel through space as much as one escapes from space or dies trying.
The BIGGEST minutiae 