It's not like the world is ending all the damn time.
It is. With every second we are getting closer to the end of the world whether it's 2 minutes away or 1000 million years.
Well, not the end of the world. The end of humanity. Nobody, even professed environmentalists, care about Earth, only its ability to sustain human life.
Incidentally that quite literal deadline is the point where we've used up sufficient nonrenewable resources (predominantly fuels, metals, &c) that we can't establish ourselves in orbit and can't maintain a high level of advanced infrastructure and industry, at which point it becomes a long slow spiral as everything decays and breaks down while our descendants desperately try to survive as pre-industrial subsistence farmers in a world wracked by the excesses of uncontrolled capitalism applied through the lens of industrial-age and information-age technology.
Developing permanent off-world infrastructure and populations is the first and foremost responsibility of any person who wants humanity to survive as a species in the long run. Unsurprisingly, nobody cares about it because people are inherently selfish and short-sighted, whether it's the self-centered but somewhat well-meaning "save the planet... for us!" end of the spectrum or the sheer unadulterated greed that is most directly pushing us over the edge.