[Semiapies]

For one, there is no "ergo, we are doomed" - quite the opposite:

"So this is why I conclude that the silence of the night sky is golden, and why, in the search for extraterrestrial life, no news is good news. It promises a potentially great future for humanity."

[TheSOB88]

I think you are reading the root comment with the wrong perspective in mind. He is saying we are doomed if there is life on Mars.

[Semiapies]

Nor is the writer saying that.