Why does the author say that the epochal and national character of culture

Why does the author say that "the epochal and national character of culture is most vividly manifested in traditional culture"?

Because traditional culture was born in the past and bears the imprint of the past era,

so it has a distinctive epochal character; because traditional culture was created by the ancestors of the nation,

it has more or less explicit or implicit influence on the nation, and naturally bears the color of its own nation.