Why was Yan Chongnian scolded so badly?

Because his speech in the lecture room was a bit defensive of the Manchu regime, with more praise and less disparagement, which caused some radical friends to be dissatisfied. At the same time, some of them were able to put on airs and lean on the old and sell the old.

But I don't think there was anything bothering him. Is academic freedom? It is understandable that an old man of Manchu is partial to his own nation.