If Dream of Red Mansions Were the History of Song Dynasty

What? Isn't Dream of Red Mansions Cao Xueqin's family affair? Shouldn't it at least be the history of the fall of the Ming Dynasty and the rise of the Qing Dynasty? How could Dream of Red Mansions be a history of the Song Dynasty? ! However, upon careful analysis, the plots of the first eighty chapters are inextricably similar to the history of the Northern Song Dynasty! Why was Jia Baoyu Huizong of the Song Dynasty? Why is the Zhen family the epitome of the Southern Song Dynasty? What is the relationship between Ningguo Mansion and Rongguo Mansion? It's scary to think about it! Intent: Interpretation of Red Mansions