Compared with the materials of western murals, the cultural relics unearthed in China are easier to preserve, and will not be destroyed even after the tombs collapse and are likely to be dug up in a few years. Western murals may be easily destroyed, and murals are likely to disappear after the collapse of buildings with murals. Maybe westerners don't realize this, or maybe they don't have enough materials, so they just left some murals.
According to ancient history, the development of our Central Plains is indeed much more advanced than that of the West, so it will be more advanced materially. Moreover, in ancient times, we were very powerful in the world. Some western countries even gave us some precious tools to seek asylum and learn our culture. Although it may be only a small part, it was already a fortune for the western countries at that time.
In addition, we can also consider our ancient system problems, about officials or rich people going to the cemetery to be buried with them. We paid great attention to this custom and system in ancient times. Officials and wealthy businessmen will be buried with a lot of money and treasure after their death. This is a tradition of the people and the court at that time, and it is also a filial piety to the deceased relatives. In the west, there may be no such thing as material burial, so the things dug up in the tomb will have no similarity at all. On the one hand, it also shows the differences in beliefs and concepts between ancient China and western countries.