The article seems to start with the conclusion that we are alone, and then work backwards from there, even though it was written in the other direction. When it comes to life, we may need to look no further than our own solar system, specifically the moons of Jupiter or Saturn.

The key fallacy in the estimate for space faring civilizations is “space faring”. Science fiction aside, space is extraordinarily hostile for living organisms, as well as their machinery. Not to mention the physics of space travel, which imposes strict limitations. We’ve only been searching for radio signals from an intelligent civilization for a few decades. As we accumulate better data on potential planets to target, the odds of a successful detection will increase. Still, having such civilizations coincide with ours in a temporal connection with their distance from us will be quite a lucky fluke.