Sorry to go all Godwin's law, but astrology can and has been used as a tool of oppression. Nazi Germany had a state-sponsored astrologer, Karl Ernst Krafft, appointed by Deputy Führer Rudolf Hess and Chief Propagandist Joseph Goebbels. Krafft was employed to write astrological propaganda that justified anti-semitism on the basis of celestial events. He was also tasked with using astrological observations to predict threats to the Führer Adolf Hitler and offer military advice.
Ultimately, it's not the stars and Moon that do the oppression, just whoever is in charge of divining their meaning, which is also pretty much how religious oppression works.