I don't think modern horror is just rehashing the old stuff. Sure, you can trace certain creature features back to regional tales, but what's more interesting is how the function of folklore got updated. It used to be about explaining the unknown and enforcing social rules—don't go into the woods, respect the spirits. Now, the horror is often internal, psychological. A story like 'The Babadook' isn't really about the monster under the bed; it's about grief and depression wearing a folkloric costume. The creature from folklore becomes a metaphor for a contemporary anxiety, which I find way scarier than a straight-up ghost story. It sticks with you longer because it's about a real fear, just dressed up in an old tale.
That said, I still love when authors dig into specific, lesser-known folklore. Silvia Moreno-Garcia's 'Mexican Gothic' pulls from real cultural history and superstition, not just generic ghosts. It gives the horror a texture and a sense of place that feels more authentic and, weirdly, more threatening because it's rooted in something real. The horror feels earned, not just conjured from nowhere.