I tried to find the discussion you are referring to, but couldn't. I don't remember it in particular. That is a depressing take. However, my personal belief is that if life isn't extremely rare, then we are likely missing the presense of more advanced life because we are observing in the wrong spectrum. As much as our technology has advanced in the last 100 years, I predict that our lives will be utterly incomprehensible to us in 500 years. In fact, I would bet that we will have separated consciouness from living matter by that point. It's my guess that life that is even just a bit more advanced than ours in terms of cosmic timescales is something of an entirely different nature. It might be only loosely tied to time and space as we know it.If we find trace of life on other planet that mean life isnt rare. So the second explanation is the correct one: we're doomed to disappear.
I think it is also important to consider the possibility that microbial life is very common, but complex organisms are very, very rare. For 1.5 billion years life on Earth was nothing but unicellular organisms. It was a gigantic evolutionary leap to go from unicellular to multicellular organisms. The conditions need to be just right for billions of years. On top of that, there have been literally trillions of multicellular organisms and only one of them has the capacity to understand the universe in the way we do.