> You've got a bit to learn about Tibet, HK, Xinjiang ( a muslim region), and soon Taiwan

Or, you've got to read to the end of the sentence:

> Mostly because China didn't conquer a bunch of neighbors and create a name for the resulting state distinct from “China”

That last part matters.

You know China doesn't refer to themselves as China, right? China is Portugese in origin.

https://en.wikipedia.org/wiki/Names_of_China

China definitely refers to themselves as China when speaking English just like the United States refers to itself as 美利坚合众国 or just 美国 when speaking Chinese.