Aren't you grateful and proud of the accomplishments and contributions of the people who came before you, that make your life today possible? When I learn about all the great thinkers who came before me, I'm inspired to make some contribution of my own, and to in my own small way help improve the world, and to try and leave it slightly better off than I when I found it.
You may not think so, but the world has come a long way since human beings first arrived. Human suffering, for some at least, has been vastly reduced, and the overall trend of violence, disease and suffering seems to be improving. If you feel no compulsion to be part of that trend, then that's your choice I suppose, but personally I feel that's a pretty good reason to justify getting out of bed.
I'd say we probably have less with respect to how large the population is. There are still many people without the basic necessities. And such necessities have been capitalized. It's becoming more and more difficult to be a "hunter-gatherer", even in 3rd world countries. I don't have time to dig up data or do a study. So that's just my guess, and to some extent, my hope!
We have become less violent, diseases in some respects are better off, and we do have large masses of minds working towards curbing and curing. We're a long way from a "healthy" society.