Such is true. The authors of the tale had to get it from somewhere, I say. A lot of people downplay the harshness of like tales, probobly to tell it to their young, sometimes to teach them a lesson through the story's moral. But others are simply folktales for tradition, or passtime. I especially see downplay of the harshness of folktales of German origin. In one of the original publications of "Cinderella", when her two stepsisters try to fit the shoes Cinderella would later wear, they cut off their toes io try to slip them on. A lot of pain, and bloodshed to try to impress a boy.
I sometimes type a tail into google, and read it from 5 different sites, or so, so I can see how different they are. I find it somewhat intreaging just how different they are. Especially when it comes to the endings, or how some events in the story were said to have happened. I gives you a whole world to think about, even more original versions of multiple tales.
Yeah, that's a pretty large reference, and I'm sure credit was given. "The Journey to the West" I'ven't read too too much on, but enough to piece it together. I won't go into detail, so as to not ruin the story for you.
Most folktales we are told, especially as a kid are usually of European origin. These tales are ones most of us are very familiar with, such as "The Three Little Pigs", "Goldylocks and The Three Bears", and "Rapunzel". There aren't many that are orally share from other parts of the world in certain parts of the world.
I've read Urashima Taro, very interesting story. I've also read Momotaro, and Kintaro, and Bunbuku Chagama. I guess next to Kachi-Kachi Yama, Momotaro is one of my favorite Japanese folktales. Issun Boshi was another notable tale I read.
I believe the Dragon Ball series is primarily based of of "The Journey to the West", which is of Chinese origin. Though there are other references to other tales near the beginning.
I usually enjoy folklore from time-to-time. So I guess you can say I have a slight interest. I've read quite a few tales from a book, but the others are by oral transmission. I recently enjoyed reading the Japanese Folktale "Kachi-Kachi Yama", and it's many variations. Although the ending is rather harsh, it was a good tale. I usually enjoy reading folktales, but other aspects can catch my eye. Such as the creature "Fenrir" I recently researched from Norse mythology.
I've read plenty over the years, but they're stories people have probably heard a million times as a kid.