Meh. Nothing lasts forever.
Why complain about it? You've already stated that you believe the car has gone off the cliff. Why not enjoy yourself on the way down?
You say we shouldn't be debating Star Wars and such because the world is gonna end in 200 years? SO WHAT?? I'll be dead by then and not becasue of global warming, but because we all have an expiration date. I'm not gonna give up my hobbies and what few joys I have in life just cause we're all gonna die (unless, of course, that would help the situation, which it won't).
My dad had that talk with me when I was very small. Death is the only thing life promises and pays off on. Deal with it!
And, no, he didn't put it to me that way :p