people who think that alien life is guaranteed are laughable. Yes, it's alltogether probable, even possible, but it is in no way likely. In fact the likelihood that even half of the events that make earth unique were recreated is already in the exponentially small probabilities. But to hit each one note for note, i mean mars was technically habital at one point, but for a billion different reasons it's not now.
I mean, earth, and life are exceptions not apart of the rule of the universe, so we are still looking for other exceptions. It's not a guaranteed.
It's just so laughable that people assume probability=certainty.