When is the contradiction between traditional culture and modern culture in China? Or when did modern culture appear around China's traditional culture?

Since the new culture movement. Westernization has artificially weakened China culture.

Supplement:

The Westernization Movement advocated "middle school as the body, western learning as the application" and took "self-improvement" as the slogan. Moreover, the Westernization Movement is mainly to solve the problem of domestic troubles and foreign invasion, which seems to have little conflict with China's traditional culture. But it should have an impact.

The New Culture Movement is a cultural movement that violently impacted China's feudal thoughts for thousands of years. Since the New Culture Movement, China's culture has been gradually swallowed up by westernization, and China almost abandoned his own culture, giving priority to western culture.

If you want to trace it back, you can trace it back to the early Qing Dynasty. The first thing that Manchu ruled China was to suppress China culture. In natural science, we don't invite China scientists to study China's subjects, but invite foreigners to teach and implement the policy of "making foreign countries make China".

Ps: I am not an expert in history. The above is for your reference only.