I've been reading Sapiens: A Brief History of Humankind by Yuval Noah Harari and he asserts that we've actually become rather global in many of the ways that we live. Sure, there are some aspects of culture that are very different from each other, but that we are in some ways, just a series of mega-cultures.
"Over the millennia, small, simple cultures gradually coalesce into bigger and more complex civilisations, so that the world contains fewer and fewer mega-cultures, each of which is bigger and more complex. This is of course a very crude generalisation, true only at the macro level. At the micro level, it seems that for every group of cultures that coalesces into a mega-culture, there’s a mega-culture that breaks up into pieces. The Mongol Empire expanded to dominate a huge swathe of Asia and even parts of Europe, only to shatter into fragments. Christianity converted hundreds of millions of people at the same time that it splintered into innumerable sects. The Latin language spread through western and central Europe, then split into local dialects that themselves eventually became national languages. But these break-ups are temporary reversals in an inexorable trend towards unity.
Perceiving the direction of history is really a question of vantage point. When we adopt the proverbial bird’s-eye view of history, which examines developments in terms of decades or centuries, it’s hard to say whether history moves in the direction of unity or of diversity. However, to understand long-term processes the bird’s-eye view is too myopic. We would do better to adopt instead the viewpoint of a cosmic spy satellite, which scans millennia rather than centuries. From such a vantage point it becomes crystal clear that history is moving relentlessly towards unity. The sectioning of Christianity and the collapse of the Mongol Empire are just speed bumps on history’s highway."
Harari, Yuval Noah. Sapiens (pp. 166-167). Harper. Kindle Edition.
He then breaks down the world into Afro-Asia, Mesoamerica, the Andean world, Australia, and Oceania. I must say, it's not a way that I'm used to looking at the world, but it is thought-provoking. He also talks about the universality of money (as well as other myths that we collectively buy into such as the idea of corporations, which only exist in a mental construct really). If you disband the corporation, the building does not evaporate, nor do the employees. Just the mental idea of the corporation.
Anyway, I appreciate your comment and am not necessarily disagreeing with you because on the micro level, it's absolutely true. I just wanted to add in this other aspect because it's kind of a paradox.