It's a bad short story. Whether it was generated at the hands of humans or a computer isn't really relevant. Speaking in riddles is cheap now, so authors better learn how to surprise the reader in simpler, more readable words. It seems to be something that LLMs are quite bad at.
Yeah, I found this extremely unpleasant to read. I wouldn't have pegged it as LLM-assisted, but I would have pegged the author as pretentious and bad at coming up with compelling analogies.
The Granta story was superslop. It's a bad writer's idea of what good writing looks like. It beat AI filters (which use heuristics that solidly classify the natural slush distribution, but fail against adverse examples) and it apparently beat human ones as well.
Sadly, there are published authors who basically stack literary devices without much attention to whether they actually work. If they're good at promoting themselves, they often get the benefit of the doubt.