"Really, all science fiction is a subset of fantasy. "science fantasy" is just science fiction that isn't actually about the science, which is the bulk of the g

"Really, all science fiction is a subset of fantasy. "science fantasy" is just science fiction that isn't actually about the science, which is the bulk of the genre." All fiction is fantasy. Fantasy is the root of all fiction. As soon as one starts to change reality, by lying about what someone said or thinking about what you could have said, that's fantasy. All labels are either useful fuzzy groupings or non-useful groupings. "High fantasy" is a label that gets you works closer in some conceptual space to The Lord of the Rings than to The Manchurian Candidate. "Isekai" is a very definite label that applies to The Lion, The Witch And The Wardrobe and does not apply to Space Quest, but it applies more to Space Quest than to most episodes of Star Trek (except The City On The Edge of Forever, which is definitely isekai, and some similar episodes.) "Science fiction" is a marketing promise that if there are elves, there will be an evolutionary heritage for them and a reason that you don't notice them walking to your local pub (no guarantees about the walk back.) Spock is a kind of half-space-elf. The space elves split into two groups a long time ago -- the ones who subscribed to a rationalist approach, and the ones who had a religion based on passion.