Some of them are exxagerrate, but others are way pretty close from accuracy.
Harry Potter? I still remember when I was little and that both Wiccans and other occult movements mediatically backlashed J.K. Rowlings for divulgating their common secrets and traditions , she's been initiated into by her family since her young age (hinting that Rowlings is one of them) .
American Gods? Primitive but complex. Neil Gaiman is all about the Nietzchean maxim "Men created Gods" and the Shaidic nature of deities within most of his artwork. It would be rather "Men created Gods, but Gods created Men" if you dig deeper into the Nieztchean Archetype theory and its both Sufi Muslim, Platonician, Judaic, Bhramanist and African roots.
Stephen King? He knows his shit.
H.P. Lovecraft?? This MOFO dipped in some nasty shit.
Stephenie Meyer and her Twilight Saga? Mormon occultism and daymares about an incubi, just literally. She's not even sleek about the latter one: she told this is how she get inspired from writting the first book.
J.J. Abrams?? "Fringe" is just basically X-Files, but with way more declassified files.
Dragon Ball?? Way more complex than it looks. Fullmetal Alchemist?? Gnoticism and Nazi theories combined. Sailor Moon?? Greek/Roman, Near Eastern, Shinto and Egyptian mythologies combined into a Gnocist study beneath the facade of some Magical Girl, borderline yaoi shojo shit... I bet one of the witches I knew even started to dig into Muslim and Wiccan occult traditions via her infatuation for fantasy genre mangas. That and the fact she was half-white.
Don't let me start about Roger Moore...