I'm sorry you feel offended by these ideas. I suggest you read any of the 3 books I referenced that explain this Chinese principal. The books are by Republican, Democratic and CCP authors.
Differences between civilizations can feel offensive.
Sounds like you're the one offended. Great 4000 year history of China is CCP party line. Reading neutral sources you'll find it's more nuanced than that.
There's some evidence remaining that China was once a collection of societies. Notably language. The CCP insists that all of China speaks Mandarin, but thats only the case since the cultural revolution.
Chinese writing is indeed nearly universal. But spoken language once had many dialects, and still does to an extent. These dialects are sometimes mutually unintelligible. If it wasn't for CCP party line they would be considered different languages, as part of Chinese language family. Much like many of the southern Asian languages are different languages that cluster together.
Differences between civilizations can feel offensive.