Well, I wasn't suggesting that life has to be common -- just that it's literally one in a hundred billion in terms of your scenario, right? I agree with you of course that it's very strange given how many planets there are out there that we haven't been surrounded by aliens since our origins. But my current thinking is that our apparent aloneness is a very strong message about the most likely solution to Fermi's Paradox: 'advanced' civilizations kill themselves off with AI or similar tech. But then wouldn't there be AI residue at the least around us or visible in terms of large-scale structures out there in the cosmos that we could detect? Or would AI simply cease to colonize once its progenitors are killed off? So many questions and so few answers. Maybe we are in a simulation? That's numerically VERY likely and it would answer Fermi's Paradox as "well, our creators put us in a universe where we are alone and who knows why".