I'm talking about the state of man in this world. Just because humans are sinners does not mean we're "evil garbage." We're not. We're children of God and all being a sinner means is that no one is perfect.
Acknowledging that no one is perfect is not depressing or pessimistic, but the opposite. It helps to understand that we're all brothers and sisters in this world, in the same boat, and should cut each other some slack.