The title is overdone. It has long been known that Israel shot down some soviet planes that soviet anti-air batteries were a big problem for Israel. Better to say undereported then nobody knew. The Secret Israel-Soviet Union War Nobody Knew About
This is a good overview for those who are not familiar with structure of Iran’s military. However, it does not make it as clear as I would like how the Revolutionary Guards Corps function as a state within a state. However, the information is all there if you pay attention. Persian Might: How Strong Is Iran’s Military?