It started as a social media post. It explains my answer to the Fermi Paradox.
Humans are perfectly evolved to their environment. Their environment is human civilization. More so, all of the things which make humanity different than the animals are fundamentally ways to be rotten to other humans.
We can't run fast compared to animals, but we can run faster than many humans -- and we can do it holding their stuff. We the ability to communicate a rich array of emotions with our face -- which we can consciously use to lie about how we're feeling. We rely about a spoken language for communication, which allows us to convince our neighbor to do things clearly not in their best interest. We have no clear signs of estrus, and we can mate for pleasure, so we can lie about the fatherhood of our children. We've use clothing to lie about our physical imperfections.
We're basically evolved to lie, cheat and steal from other humans.
It's like a biological basis for original sin, where the ability to know all of these higher-order things is tied deeply to our ability to commit evil. (Religion, then, at its best acts as a filter to tie us back to the kind, social animals of our beginning.)
This would be the filter preventing intelligent life from reaching higher states. It becomes exceptionally hard to escape the fact that you're evolved to be evil to your kin. Backstabbing and distrust is basically baked in to the design. Your environment is your own civilization, and the natural impetus is to become a super-predator there.
It is deeply human to be rotten to each other. The exploration of this rottenness, both in fiction as well as non-fiction, is what daytime television is made of.
Evolution doesn't just stop because you've mastered your environment. It doesn't stop when you've mastered it locally on-planet, and it doesn't stop when you've mastered it and you can play with the stars themselves. Until a race stops having children, it keeps evolving. Shoot, even without children, if people can upgrade their physical form, there's still the ability to evolve.
From an extraterrestrial-visitor context, things go from bad to worse, as the likelihood of other life having solved our problems decreases. Militarized states and power struggles, the abuse of the lower classes, these become universal to the point that surviving them may mean mastering them in ways we've not considered. The notion of extraterrestrial con artists buying planets for baubles becomes all too realistic.