Could play out many different ways. There’s nothing inherent about a classless society that would necessarily result in one or the other. And there are many degrees of subcultures within a so-called monoculture, for instance, there would still be a “fishing culture”, “student culture”, etc, as people are naturally split into different sections of society based on their role in it. There just wouldn’t be a split based on class. But other non-antagonistic roles would still exist.

Someone can correct me if I’m wrong but communism isn’t the end of history. There will be still be human progress after communism is introduced in different ways, different cultures being created, changed, or disappearing. It’s just that the class contradiction and all the contradictions that follow from that will no longer be a factor.

As Marxists we cannot ask the question of what a classless, moneyless, communist society would look like without first examining what may come before it, which would be a socialist transitory state.

Say that, in the somewhat near future, socialism’s final victory has been won. Africa is free of imperial tentacles, America’s empire has collapsed, and Europe has abandoned its capitalist ways. In most if not all nations, the workers own the means of production, and a dictatorship of the proletariat dominates the bourgeoisie and oppresses them. Now we must begin to ask the question: what next? And then we must ask: for how long?

In a system free from the tendrils of capitalism, socialism would be allowed to exist and develop unopposed by naval blockades or sanctions. Humanitarian aid, developmental subsidies, and reparations would be delivered to underdeveloped areas of the world—without strings attached and without CIA weapon and drug shipments. It would not be unlikely to say that travel among nations of the world would increase dramatically as people migrate for jobs or become refugees in more developed nations due to however torn their own country may be due to the events of the world revolution. Without the capitalist conception of border restrictions, abuse of cheap migrant labor, and a true sense of proletarian internationalism it is likely, in my mind—although it is conjecture—to say that over time many people would travel all over the world for various reasons. Especially when the exorbitant costs of travel would be lowered, and as the world recovers from the climate crisis brought about by the previous capitalist world order.

In this socialist world, where travel is more common and freer between nations than ever before, where nations begin to wither away their state apparatuses, and in turn the borders that segregate them, countless cultures would meet each other. Not in a competition, not in an existential war, but in peace, and in mutual respect and a shared love for each other in the way humans were meant to be. It is not to say that socialism would be everyone holding hands and singing kumbaya immediately. There will be conflicts, disagreements, and antagonisms between groups, but as the contradictions within socialism disappear, so too will these antagonisms. Think of multicultural and multiethnic examples set in the USSR and Yugoslavia, but over the long term. Over time, these cultures would embrace each other.

The length of time this blending occurs is exactly what we would need to know for the crux of your question to be answered. In my mind, which anyone is free to disagree with, or to present evidence against: no one nation can simply do away with money on its own. Even under socialism, it would be a cultural cold water shock to people who are familiar with money as a unit of trade to simply legislate it away. It will take at least a few generations to undo the parasites of capitalism in the collective consciousness, and to completely do away with money would take even longer. I believe that when the truly classless, moneyless society is born from the womb of socialism, and all states have withered away and died, and all men and women are free to live in peace, the cultures of the world would have blended together dramatically more than we have today. Many of them will be preserved, but not necessarily in their original state. Many cultures would change as they are exposed to new ideas and shaped by their newfound material experiences under socialism. New cultures will be born, and many old ones will die. The Communist society of the future is one that will be multicultural, but in a fundamentally different form than multiculturalism takes today.

Freed from the shackles of wage labor.