If the universe is essentially "nothing" in the grand scheme of things, then why do people worry so much about "wasting life"?

I hope you'll excuse my skepticism about the meaning of life and my lack of faith in humanity's ability to achieve greatness. It seems like a universal constant that people like talking about the fleeting nature of life and the universe, but then act as though it's the end of the world if they don't contribute something of value, achieve something great, or make the most of their time. I think it's interesting to consider that the universe is ultimately nothing more than a vast expanse of emptiness, and that our existence is nothing more than a temporary blip on the radar of time. What are your thoughts on this?