What is the relationship between the implicit beauty of China's poems and Confucianism?

The Confucianism you said should be generalized, and the narrow Confucianism is relative to Mohism, Taoism and Legalism.

Confucianism in a broad sense is all our cultures.

Implicit beauty is because we like indirect and vivid expression, which makes people think. Poetry is an art form, so are other art forms, such as novels.

Our culture encourages people to get along directly, but in order to avoid confrontation between people, we have invented many implicit ways to get along. Etiquette is typical.