Why can Confucianism become the authentic traditional culture of China?

Confucian school catered to the needs of feudal rulers who advocated Confucian culture.

The "Confucianism" advocated by the autocratic monarch in China since the Emperor Wu of the Han Dynasty is actually not the original Confucianism in the pre-Qin period, but the pseudo-Confucianism theory created by Dong Zhongshu after the transformation to meet the needs of the autocratic rulers. Autocratic tyrants are not interested in or even disgusted with the real primitive Confucianism (the thoughts of Confucius, Mencius, Xunzi and others). Primitive Confucianism pursues retro, demands self-denial, opposes arbitrary expropriation and oppression of the people by the ruling class, opposes foreign wars, and opposes the use of harsh laws to govern the country. Mencius even had revolutionary ideas that people had the right to resist and overthrow thieves. In this way, Zhu Yuanzhang hated Mencius and cleared him out of the Confucius Temple.

Dong Zhongshu and his later Scholars carried forward the dross of pre-Qin Confucianism, tried their best to maintain the unequal social hierarchical order, took the unequal social relationship of "monarch, minister and son" for granted, formulated the ethics and social norms that oppressed the people, and opposed all social changes that might lead to the destruction of the hierarchical system. This theory actually serves the autocratic monarchy system, adapts to the needs of autocratic monarchy, and is conducive to paralyzing the resistance of the lower class to the ruling class. It is an important public opinion tool for the ruling class to maintain its dominant position, which is naturally favored by the rulers and regarded as the official ideology.

In addition, the later "Confucianism" also had some positive influences. For example, the Confucian world outlook is conducive to the development of a multi-ethnic unified country, the sinicization of ethnic minorities, and the maintenance of Chinese civilization. After constant annotation from Dong Zhongshu to Zhu, the Confucian Four Books and Five Classics emphasized the "orthodoxy" of the dynasty. This "orthodoxy" is conducive to maintaining the political system of the family and the long-term stability of the dynasty, adjusting the internal relations of the ruling class and easing the internal contradictions of the aristocratic landlord class. In a word, Confucianism after the Han Dynasty is beneficial to the ruling class, that is, to their oppression of the people and to maintaining their internal stability and unity.