There are a lot of thought experiments, such as the fermi paradox, that seem to provide a "logical" explanation for why signs of other civilizations haven't been observed.
Funny thing is though, if there's one thing scientific exploration of the world and the universe has done time and again, it has been to knock humanity off its pedestal.
The world was not created for man. The sun does not revolve around the earth. Humanity is like all other life on this planet. The conditions for physical existence are the same throughout the universe. The discovery of exoplanets now increasingly provides examples of the same principles playing out countless times across the universe.
The pattern suggests that life is hardly unique either, and that includes intelligent life. If anything, I'm willing to bet this:
That not just life, but forms of intelligence, are entirely common in the universe. That life is everywhere. And if humanity hasn't detected or correctly interpreted evidence of this in just a century of pointing stuff at the sky, the fault is with humanity for simply not understanding something yet.