Every beginning is weak, and martial arts need long-term accumulation and refinement in order to develop. What Zheng Yichen did was 'dumping' in this area, making the human race increasingly dependent on their martial arts in the long run.
Yet, it seems this world had not developed to that extent, and since Wei Xue brought it up at that moment, it must be related to the heart laws he was talking about now.
"The wise ancestors of the human race created various heart laws to eliminate hidden dangers, which could be seen as an indirect solution," Wei Xue said with some emotion, "The Supreme Demon and the demonic tribe did not 'hide their skills,' leaving no fertile ground for the development of the human race's martial arts."
"The existence of heart laws significantly reduced the hidden dangers of these non-human martial arts, and under such circumstances, the human race gradually developed its own martial arts," he added.