I had occasion last night to wonder how much of China's real history is left now. I've spent a lot of time in Korea and know that the Japanese were particularly thorough in stealing or destroying as much of the historic material as they could during their decades long occupation. Every museum except the one I visited in Mokpo had a number of empty spaces in the display cases with a card reflecting that the item that once adorned them had been stolen by the Japanese. I figure the same thing must have happened to all of Japanese occupied China.
Then there was the long war between the communists and the Kuomintang which didn't really end until 1949 and still sees the remnant of the Kuomintang occupying Taiwan with whatever they managed to pack up and take with them when they fled the mainland. Who knows what they have and what was buried, hidden or destroyed by them before the left China forever.
And yet even before the ruin and destruction of the Japanese invasion, the Chinese themselves overthrew the Empire and established a Republic and who knows what vanished as the final empire in China disappeared into the welter of civil war, the Boxer Rebellion, confusion and outright theft as treasure hunters made deals that many must have found hard to refuse.
Perhaps the worst of the trashing of Chinese history was done by the communists themselves after they finally drove out the Republic and then instituted the 20th century's years long curses of the Red Brigades and Red Terror and the Cultural Revolution. I suspect a lot of China's history went up in smoke or was hidden away by caretakers who might not have survived and so never returned to salvage what they had tried to shelter from the antifa and the SJWs of their era.
It's probably a good thing that a number of Orientalists got in there early enough to make a record of what the history was before it was swept away. The thousands of years of civilization is on par with the thousands of years of Egyptian history. You'd never know it existed to visit Egypt today. There is precious little of it left that was small enough for the conquerors or the people to pick up and carry away and Nassar and the rest did a fine job of wasting or destroying those things that were too large to carry off.