Given the extreme age of the Galaxy, extraterrestrial civilizations should have occupied every corner of it by now. Yet we see no signs of this. A short new video produced by New Scientist beautifully explains why the Fermi Paradox is a very real scientific problem and why it should be taken more seriously.
This video annoys me. We just don't have enough data to say anything meaningful. We can't even say if the Fermi paradox is a paradox and likely won't be able to say if it is for a long time. First of all, the age of our galaxy (which is almost as old as the universe) doesn't really mean a lot. It's very likely that complex life wasn't even possible until a significant number of first generation stars went supernova because heavier elements required for life would have been too rare.
Then (based on Earth at least) it appears that going from single to multicellular life is very hard. It took a lot longer for that than it did for life to appear in the first place.
Also, there is a good chance that planets too close to the galactic center aren't suitable for advanced, intelligent life because there is a lot more mass there and a lot more events that would negatively impact the development of advanced life.
Also, some researchers think that the likelihood of intelligent life evolving is very low unless a planetary system has one or more gas giants in outer orbits to help "protect" the inner rocky planets. Most of the systems we have found so far have gas giants that are very close to their parent stars, the opposite of our solar system.
There are tons of reasons we may not have found advanced civilizations yet even if they aren't out there. Seems silly to draw any conclusions at all for the foreseeable future.