But we actually showed up after 3 billion years of evolution, because our planet is only about 4 billion years old. Consider that most habitable planets will have wildly different ages- some might be a few thousand years ahead (or behind), some might be 5-10 billion years older than ours or may have only formed in the last 2 billion years. What are the odds we would all evolve to spacefaring within a few centuries of each other?
But what if the conditions for the evolution and prolonged survival of advanced civilization (which is what we are) only exist in the older, cooler, less dense universe in which we find ourselves today?
Personally, I do think there is life out there but even if it has advanced to the point where it can break atmosphere, there are immense volumes of space between us.