Every era of humanity has been convinced, at some point, that it represents the end times - either as the peak of experience, evolution, and development, or due to some mumbo-jumbo apocalyptic superstition. So it would be hubristic for our modern convictions to be seen as extraordinary. The differencemaker now is that we have more than enough stats indicating ecological collapse that our dourest forecasts have a greater likelihood than, say, a wolf eating the sun or the dead rising from their interment.
So while people have always considered and contemplated their own mortality, apocalyptic fiction, especially depicting any kind of eco-Armageddon, inevitably must face the very real possibility that we may be gone, as individuals and as a species. How do we face that ending?