I can agree with Fermi's paradox on one level. However it has one giant flaw.

It assumes that any and all intelligent life will have the same agenda, the same thought processes, the same technological ideas, creations, advances.

Robots might be a unique creation of the human mind, especially the self replicating one. There's a ton of reasons why alien civilizations would NOT colonize the galaxy, either because they could not or did not want to.

Anyone watch Farscape? The species that Pilot is is unable to leave their planet without the help of the bio-mech ships(Moya). What if there are species like this who are just incapable of leaving their planet? Insect-type species? Maybe intelligent life really is unique. Any kind of life out there will be astounding whether or not it is smart.