Nothing that I will ever say or do has any lasting meaning. Whether I pick a black or white shirt today, whether I donate to charity or not, whether I murder a child or save a life, the odds are that in 10 trillion years it will have made a total difference of 0.
Whatever we do, ultimately, has no meaning. In the grand scheme of things, we are but a tiny speck of dust on a meaningless planet in a meaningless universe drifting silently through vast cold space. Reanimating dying people, curing cancer, trying to find a formula for immortality, hell, any medical or engineering advances made by humanity make absolutely no difference.
Life is inherently worthless because it has no objective purpose or value. Why would anyone choose to live? Happiness, procreation, advancement of the species are all empty answers. Especially happiness, since it’s just an empty concept that gives us an illusion of worthiness. People delude themselves in thinking that life is meaningful and beautiful.
While perhaps insignificant in the grand scheme – you’re likely very important to lots of folks in your own little microcosm. Plus – I think you’re underestimating the human race – I think we’re on the cusp of mattering, given the technological leap in the last century. These are exciting times. If we do indeed manage to escape this rock (essentially at least doubling our chance of non-extinction from anything but galactic scale disasters,) I predict big things for our future.