Textbooks are aimed at popularization, not specialty.
As a politician, Dong Zhuo has only been in a hurry for a few years. It is obviously difficult for such a passerby to occupy the title page in a history textbook with only more than 200 pages.
During the Three Kingdoms period, only monarchies like Cao Cao and Liu Bei were allowed to go to textbooks. After all, although the Three Kingdoms are legendary, they are just a drop in the ocean in the long history.
If the landlord wants to know Dong Zhuo, he can read more professional history books, which are recorded in detail in the annals of the Three Kingdoms.