Culture in the TL is different than it is in OTL. Yet the definitions are the same though. The first definition is that culture is a shared collection of attributes, values, beliefs, goals, practices, and ideals that foretells how a society, organization, or nation is like. The second definition is that it is the set of the arts and humanities. Regardless of definition, culture is considered an output of human creativity and civilization, which has always depended on the environment. Culture is considered to improve or cultivate one person in some kind of way though.
Because there are more, much larger nations (and with that fewer nations) in the world, existing cultures in the TL are far grander and different than OTL, though foreign influences always can have the ability to shape it. For example, French culture has been the most famed and most widespread culture in the world, which is common in Europe, the French Empire, its former colonies, and other countries. Yet it is also shaped by the influences of other European countries, partially Russian, British, Spanish, Italian, German, Scandinavian, Greek, Arab, and Turkish. The second definition explained on the first paragraph also reflects the shaping of culture, which is what has shaped American culture. Although people consider themselves Americans in the country, they have been descended by a wide variety of ethnic groups and have adopted and blended in with numerous different cultures, notably from Europe, Latin America, and to a smaller degree, Asia. As western civilizations, the French and Americans have believed that their cultures are superior to all others, which has led to worldwide colonialism and the westernization of China and Japan. The process of assimilation and modification has shaped the history of western cultural development for the modern era.
While culture has spread to other cultures (and the other way around), some people who follow a certain culture tend to scorn foreign cultures. For example, the Malians and Ethiopians, while endorsing the western world and its technology, has scorned western culture has inferior and dangerous to their culture and society. To counteract this, they encourage people to stick to their cultural ideals and scorn foreign influences. Others nations, such as those in Africa and Asia often blended foreign influences with their culture. For example, in Hindustan, China, and Japan, while people still follow their native cultural values, they have been accustomed to western culture as well, such as media, clothing, and food. Despite western influences, these cultures have never truly given up their traditions. In fact, to these nations, forced cultural isolation has failed, and the people should give in to the influence.
Regardless, France and America have also prospered by foreign traditions, which have often benefited rather than weakened the countries when they accept cultural values not from their own.