1.His rank is a military rank , not a civilian rank. So he is supposed to fulfill a soldier's standards and task. He is supposed to command a military unit and fulfill its task, though it might not be a front line fighting task.
2.Obviousely Mao can not fulfill the basic standards of a military man.so his general rank is a joke from any point of view out of china.
3.communist party traditionaly being not seriouse about military forces, just they are not serioue about China's territory.
毛泽东嫡孙毛新宇升少将 作家学者批评