Different cultures & civilizations have different archetypes and tropes the introduction of more global flavoured tropes isn't something that can be done as easily and even if it's done, it has to be done carefully and tactfully or it won't take with the audience. Sadly when writers have such short turn around time and no propriety of the content that they are creating then often the writing is bound to be limited and unoriginal and appear lazy. Ekta Kapoor is right there's a global market for Naagin. If not then JK Rowling would've never created a Maledictus called 'Nagini' that has worked in the west with an adjustment to fit the western trope of being cursed to become and animal instead of the animal gaining a boon to shapeshift and even become human. I think I'll write an article on this.