It’s nonsense; most of the films are. They cherry pick cool bits of the occult and plaster them in to suit the plot, it doesn’t actually mean anything interesting or useful as far as real occult practice goes. This one seems a bit derivative from Omen.
I doubt even the costume designer knew what it was. They probably searched in the Internet for “demon image”, bought a pendent off Etsy and went “that looks cool and spooky, let’s use that”. The film has nothing to do with Paimon, so it’s just a prop.
But I’m generally snobbish about horror movies as as rule, they are all only ever disappointing for me as they always take shit out of context and make up silly behaviours just to fit the plot which annoys me…
Now, Thomas Sheridan is an occultist I respect, with an interest in psychology. Though I don’t always agree with him he’s thoughtful and very well read and informed, and he thought it was an interesting occult and psychological horror movie, and has a very interesting review from a practitioner’s perspective. Plus he actually watched it
It’s just a film based very loosely on occultism as a driving force for the creators to discuss cults and generational trauma. Annie doesn’t know what the necklace is or means, that’s part of the point of her discovering the photo album of her mother’s cult and the chapter book about Paimon (which was mostly made up to work in why Charlie’s death was important).
The noises I thought were clever, and at the ending the background music becomes so loud that it almost hurts the ears — goetic and demonology entries about Paimon often say he is accompanied by a thunderous parade of trumpets and musicians announcing his presence. Otherwise, some of the noise in the film is just sound design to grab your attention. As films always do but you may not notice due to how intentionally subtle and natural they are.
It’s just a movie. But it does have some fun little occult bits peppered in.
All those movies are from a stereotypical Hollywood perspective as previously said. However, Hereditary is one of my favorite horror movies. Everything from the acting to the camera angles was very well done IMO and had a disturbing feel to it.