"Three points in the world" actually shows that Cao Cao has won the world. In fact, even the last Sima family can't explain anything. At that time, Cao Cao's rights and status were the best in the world. It can only be said that he didn't claim to be the emperor, but Cao Cao's failure to claim to be the emperor is actually a cover-up, and he doesn't want to die under the pretext of "holding the emperor to make the princes", which smells like stealing clocks. In fact, his power is above the "emperor".
Cao Cao crusaded against Dong Zhuo, making him embarrassed to be emperor for fear of being reviled by the world. He crusaded everywhere under the banner of supporting the Han Dynasty. If he proclaimed himself emperor, it would appear that he was an unknown teacher. If he doesn't claim to be the emperor, he is actually a "memorial arch", which doesn't affect that he is more powerful than the emperor. In fact, not only Cao Cao, but also Sun Quan and Liu Bei were very cautious when they proclaimed themselves emperors. In the past, under the influence of imperial power, being an emperor was still a taboo thing. Cao Cao left the opportunity to be emperor to his son in the form of abdication, and the reason was because of Cao Cao's contribution, which was not much different from being emperor himself, but a trick.
If Cao Cao proclaimed himself emperor at that time, under the influence of imperial power thought, it was a typical disloyalty and unfilial, just like Dong Zhuo, the phenomenon of begging in the world would appear again, and Liu Bei and Sun Quan were more likely to send troops together, because when Cao Cao controlled the Han Dynasty, he could also comfort him by raising Sun Quan, who was an official of the Han Dynasty, especially Sun Quan.
As for Sima Shi's seizing the throne from Cao Fang, it is actually similar to the Qing Dynasty's seizing the Ming Dynasty's throne from the king. In the name of justice, in fact, the tactics of ancient emperors were very particular. It takes a long time to measure, and they are all experts in this field. These are all comprehensively expounded in Mr. Li Zongwu's "Lara".