>>7145
I see the argument, but consider that while many civilisations have fallen or disappeared mysteriously, like the Mayans, Indus Valley civilisation or the great bronze age collapse in the Mediterranean, non of those places became completely empty of people because of this. Not even in the short term. There is a big difference between a civilisation collapsing and the species dying out. Considering how adaptable humans have been to even the harshest environments with the lowliest of tech bases, like eskimo tribes surviving in a frozen wasteland or aborigines surviving everything the australian wastelands attempts at killing them, I doubt that even all electrical machines instantly stopped working tomorrow and all humanity was plunged into a stoneage within a generation, the species would still survive.
And I don't see how this wouldn't hold true for aliens.
There's options for wiping ourselves out, like nuclear wars (which I personally doubt would actually exterminate humanity and not leave at least a few survivors), grey goo and so on, but the problem is that no matter how terrible the catastrophe, once we get off the planet, the odds of the species being wiped out by anything less than a concerted effort by someone else, become fantastically small.
A far more disturbing answer is the simulation hypothesis. A hypothesis made all the more likely, since any species that gets big enough to simulate universes full of sentient beings, could inevitably simulate millions if not billions of them, given enough time. So simulated sentient beings might well end up outnumbering real physical beings doing the simulating by trillions to one, the rest is simple statistical probability.