I would think that it's shortsighted. Just on Earth, we've been through several millions of years of various evolutions. We've had fauna, mega fauna, mega flora, dinosaurs, so many things have occurred over millions of years. It's hard to believe that none of this has possibly occurred elsewhere.
You're talking about evolution, I'm talking about life forming. More specifically, think about the likelihood of a cell forming from purely chemical reactions and kinetics.
Edit: for clarity