I guess I'm more of an optimist than you guys, but I also don't think I'm being totally unrealistic.

Our species can potentially learn to live with nature, or at least not interfere as much. We could solve psychological and social issues. Cure cancer, aging, dying. We could learn the mysteries of the universe.

The fact that these things haven't happened yet is not a reason to expect that they'll never happen. 500 years ago the scientific method didn't even exist, that's a drop in the bucket in the history of life on earth. Even with all the fucked up shit that happened during that time, we've accomplished a lot of cool things. Barring a catastrophe, it doesn't end in 2021, and will continue after our generation dies.