Very interesting observations. But what I find most interesting is the perspective and the tone of the author, as well as the contributor, regarding the subject. First and foremost, the title is humorous because it implies that there is some scenario in which homo sapiens will NEVER go extinct. Our species, like millions before us, will certainly go extinct one day. Period. The second item I find interesting is the way the author, like so many environmentally concerned thinkers, pit "Nature" against humans. Does he mean to say humans are supernatural, and did not evolve as an intrinsic part of nature? I have no doubt that humans have been taking a larger and larger degree of control of our macroscopic environment for thousands of years, but I am just as certain that other species would (and do) fill any gaps immediately. Humans have been winning the struggle for dominance only if you look at coral, rhinos, spotted owls, etc. Those horrible things that might happen if humans suddenly went away - should not concern us, because we will be gone! And if extra radiation lasts 100,000 years, that is the blink of an eye for mother Earth, and far less damage than would be caused by a major asteroid or megavolcano. Many species - viruses, bacteria, fungi, insects - are doing fine and will do just fine with or without homo sapiens!
I cannot help to see that environmental science writers, no matter how scientific and objective they claim to be, continue to hold the (often unconscious) bias that humans are outside of nature. Once upon a time deep thinkers of all cultures attributed this separateness to a belief in superiority of humans due to their relationship with their deity(ies), and those deities bestowed caretaker duties on humans, and just humans. Now, in the twenty first century, even the most ardently atheist scientists cannot seem to shake this intrinsic bias that humans are not part of Nature but the anointed custodian of Nature, a concept that originates in the religions whose tenets they try to deny.