Thank you Philip for the very interesting information!
Reading your explanation I remembered another very interesting aspect:
the museums in China have very small collections of Chinese porcelain.
And this is because of two main reasons:
1. throughout the whole history of China, porcelain was a main export product and was exported in massive quantities;
2. during Mao's "Cultural Revolution" porcelain has been considered as a symbol of aristocracy and decadence and was systematically destroyed.
So I was thinking that maybe the "Cultural Revolution" thing may have impacted the jian swords as they also were a symbol of aristocracy.
