It will take more than one post to explain why I don’t see Revelation 12 the way you do or see it as relevant. Genesis is about the past and Revelation is about the future. Why do we have to consult a scriptural book about the future to understand a book about the distant past?
Here is an explanation of what the Devil being cast down in Revelation 12:9 could mean, one different from what you are used to hearing. The Devil being in the heavens could mean that he and the ideas he puts forward are on the world stage, they are influential. When the Devil is cast down, this would mean that the Devil’s influence over the hearts and souls of humans is being curtailed. After being cast down, the Devil is not as dominant, although he has influence in many places on earth.
If this sounds a bit vague, one possibility is that the Devil being in the heavens refers to the dominance of paganism, polytheistic religion and idolatry. At the time John wrote Revelation, the Roman Empire was worshiping multiple gods, and using idols. In the next few centuries, polytheism was set back quite a ways. Today, for large parts of the earth, monotheism is dominant. That could be the meaning of Satan being cast down.
Scholars say that Genesis was written, or composed, around 1000 BC. Revelation was written around 100 AD. So Revelation is about 1100 years after Genesis. When trying to understand Genesis, why do we have to go to a book written 1100 years later? Are you telling me that no one knew what the story of Adam and Eve was about until Revelation was written, 1100 years later? I don’t think so.
Revelation wasn’t accepted into the canon of scripture for another couple of hundred years, so instead of 1100 years, we could say 1300. Most Christians weren’t reading Revelation until after it was accepted as scripture.