You miss the whole point of what creativity is about.,
Using the examples you mention, they aren't successful because it's about magic and different worlds.
They are successful because they are about relationships, the difficulty of growing up, being different, overcoming hardship. I could go on, but I don't want to belabor the point. The common elements to susccessful stories is that the audeince can relate to the characters,
"No one understands me. Why am I different? People hate me because of who I am. It's good to have have friends and be trusted.
Characters get people hooked and invested in stories and if the writer is skillful enough the environment becoms a character also.
Also stories make statements about current events. From Gulliver's Travels and Game of Thrones in books to Star Trek and Black Mirror on tv.
So no, I've never been to Faityland. However, I can write stories about characters who struggle, succeed and fail. Who have to exist in a political cal system that doesn't help them like it is supposed to do. Fairies who are killed because they have purple wings and not yellow. Wnating to grow up and not having adults tell them what to do.
Whether you agree or not, there isn't a good story you can choose that is not based on the human condition and our struggles. if you've had to fight fir a promotion at work and choose to tell that struggle in a fantasy setting, where jobs don't exist, that's great. Someone else has fought for a promotion or seen others do it and they will relate, as well as enjoy the swords and dragons along the way.
Yes, Virginia, there is a Santa Clause.