Apocalyptic movies are usually so stupid and unscientific they give some kind of false reassurance. These physically incorrect things won't happen in real life, will they?
Not in the Hollywood way, sure. But sentient life will be wiped out if goes on as is. Mass extinctions are part of the natural course of events in Earth's history. Ordovician–Silurian extinction event: 60% to 70% of all species dead. Permian–Triassic: 90% to 96% of species. Cretaceous–Paleogene (that one with dinosaurs and an asteroid): 75% of species. The next one is on the way, in whatever form it comes, and even if man as a biological species survives it, the incredibly complex and interdependent system that is modern civilization will collapse.
That means sentient life shouldn't go on as is.
Humanity's goal, as I see it, is to create an alternative, disaster-proof civilization. A population that can survive extreme temperatures, radiation and toxicity, consume fuel when there's no organic food, live under water or in space. Yes, space colonization will actually be possible with such enhanced humans, while current human bodies are damaged even by a short term in an orbital station (muscle atrophy, immune system issues etc). Even flights to the stars will be still highly improbable, but not completely unfeasible.
I say 'enhanced humans' but they don't have to be our biological descendants. What about a non-organic civilization inheriting our knowledge and taking it to the stars, or a genetically engineered mix of several species? Appearance or origin aren't so important, result is what matters.
I can see problems in that future (that sci-fi books like Schismatrix describe), but everything is better than simply existing until the next asteroid hits and all our hard-earned achievements go down the toilet. In today's life, I'm for all that works towards that objective and against every hindrance. Even though it's a faraway dream, we can benefit in our lifetime just from pursuing it, 'cause technological development makes life more and more comfortable and interesting all in all.