The "5,000 year" claim is based purely on mythology. The archeological evidence makes 3500 - 4000 years more likely. In other words: the mythical events that happened 5000 years ago were likely oral history retellings of events that actually happened 3500 - 4000 years ago. Chinese history history certainly isn't much older than about ~2000 BCE, and that was prehistory as Chinese writing didn't develop until around 700 years later.

While writing was developing in China, the Great Pyramids were already 1,000 years old, and the great city walls of Uruk were 1500 years old. Cuneiform writing is older still. Göbekli Tepe had already had its golden era and had bee abandoned for 6500 years by the time the first writing started to develop in China.

China is not the oldest civilization. It is barely even in the running, and only if you take the mythological 5000 years at face value. Comparing archeological evidence, ancient china isn't actually that ancient, compared to the Middle East.

I know it's widely believed there that China is the oldest civilization. But it's a laughable claim.