Warring States: Guiguzi local Guiguzi, did this person really exist?

Warring States Period: Game Description of Guiguzi: During the Warring States Period, an old man (real name Wang Xu) lived in seclusion on a mountain called Qingxi Guiguzi (now Hebi City, Henan Province). He studied, meditated in the mountains every day, lived an isolated life away from the world. However, for more than 2,000 years, strategists respected him as a saint, strategists respected him as an ancestor, fortune tellers respected him as an ancestor, and Taoism regarded him as the ancestor of Wang Chan.