Could be the “Dark Forest” theory. That theory suggests that we haven’t been contacted because other civilizations have either been destroyed by a more advanced race or they are all hiding. And we just haven’t been discovered yet by this advanced race.
Discovery of us means a casual attack resulting in total extinction of life or the possibility of life in this solar system - best plan guaranteeing success is causing the destruction of the Sun.
We do not want to be found and if we find Someone we must destroy them before they do the same to us - a tenant of the Dark Forest theory, not my idea. For inquiring minds, please don’t ask for the details or reasoning - they are available on the web.
You cannot hide from them. It is their galaxy. And it is not called the Milky Way. Lol.