A long read introduction to the topic - from We Want to Believe: How Aliens Went Mainstream and Why It Matters
“The search for exoplanets is radically expanding our understanding of the cosmos. “We have learned that the universe is teeming with a fascinating variety of planets, more types than we could have imagined,” writes the astrobiologist Lisa Kaltenegger. But so far, it has found exactly as many extraterrestrials as radio astronomy has: zero. The more we learn about the universe, the more acute the Fermi paradox becomes.”
I like the theory that any life advanced enough to explore the galaxy is watching humanity in disgust and avoiding us like the plague while waiting for our self-induced extinction.