I think we've only begun to scratch the surface really. Most space horror is just being stuck in a place with a monster. It's just a reskin of fantasy, not that different from being stuck in a labyrinth with a minotaur.

Very little space horror explores just how horrific the sheer difference between us and whats out there can be. Stuff like Blindsight or Annihilation.

Or even just contamination horror. You are literally made out of food. Every single moment of your life a horde of microbial life is trying to eat you alive, parasitise you or highjack your cells to force your body to create copies of itself until your body simply fails.

The only reason you're not a failing mind in a decomposing living body right is that your immune system has learned to fight off most other Earth life from eating you alive.

Any life you encounter out there will be unfamiliar to your immune system.