Do you have additional information about that incident?Yuan was a legitimate Chinese dynasty, period. Even Ming's founding emperor, after kicking the Yuan out of Beijing, put Kublai's name in the shrine for China's greatest emperors. I fully stand behind the Chinese government's refusal to provide material for promulgating the Western narrative. If people in the West are so wrapped up in their story about other people that native perspectives become 'not understandable' to them, it's their loss.
BTW, in China today it's the Han supremacists who insist on denying Yuan's Chineseness. In fact, the Han supremacists' take on Chinese history bears striking similarity to the Western narrative, which isn't surprising considering the West was the birthplace of Nazism.