From the article:
“Statistically speaking, the odds are very much in favor of their being millions of civilizations out there.”
That’s where all these Drake equation / ETI predictions go off the rail. Statistically speaking, we don’t know diddly about the odds of the existence of intelligent extra-terrestrial life-forms - there could be a gazillion of them, or there could be just us.
And we don’t know because we don’t know in detail how intelligent life evolved - and if we don’t know that in detail, we don’t know the odds of it happening, even on an earth-like planet orbiting right in the sweet zone of a Sol-like sun. There could be 10^20 such planets, but if the odds of intelligent life evolving in such a situation are one in 10^21, it’s just us. And if those odds are one in 10^10, there’s gonna be critters everywhere. But we have no earthly idea what number would be.
No harm in looking, but if SETI’s your thing, prepare to be disappointed if nobody’s around to pick up the phone.
This is another major problem with the Drake equation analysis. It is difficult to define 'earth-like.' One needs a list of ALL of the attributes a planet must have in order for life to be possible and one must also know the likelihood that a planet formed by happenstance would have every one of these attributes within the necessary tolerances. Some estimates of this 'fine tuning' suggest it is very unlikely that even one planet would exist so hospitable to life as is the earth.