Zees: THat may be R’ Miller’s view. Others have a different approach. R’ Hirsch argued that God intentionally created the world imperfect, and He want us to make it better. He created perfect conditions that we can use to make the world better, but the world is not as it should be. The Ramban in Bereishis alludes to a similar idea.
True, its not good to to be a grouch, bear a grudge, and generally be depressed at the state of the world. But that doesn’t mean we should think the owlrd is perfect; it obviously is not. Instead of talking about how bad thing are, however, we have to ACT to make them better.