It may just be hyperbole, but I don't think you can rule out a dead planet. Aside from a few extinction events in which the vast majority of life on Earth did

It may just be hyperbole, but I don't think you can rule out a dead planet. Aside from a few extinction events in which the vast majority of life on Earth did indeed die, the climate has changed slow enough for evolution to take its course. If what "naturally" would've happened over the course of a million years instead happens over centuries or even decades years then things become much more bleak.