Why are loyalty and filial piety interlinked in China traditional culture?

In fact, in the traditional culture of China, the so-called connection between loyalty and filial piety refers to the behavior of some children of those, er, senior state officials. In fact, for many poor people, it is difficult to be loyal and filial. If you choose filial piety, then you can't be loyal to your country and have respect for the people led by your boss. If you choose Chinese medicine, you won't have a filial piety to your parents.