Jesus Christ is good for the world because he came as the life of the world. You point out, rightly, that loving our neighbor as we love ourselves is impossible for us, completely out of our reach. But you take this inability as a state of nature (which the commandment offends), while the Christian takes it as a state of death (which life offers to transform). Our complete inability to do what is right does not erase our obligation to do what is right. This is why the Bible describes the unbeliever as a slave to sin or one who is in a state of death. The point of each illustration is the utter and complete inability to do right. We were dead in our transgressions and sins, the apostle Paul tells us. So the death and resurrection of Christ are not presented by the gospel as medicine for everyone in the hospital, but rather as resurrection life in a cemetery.The way of the world is to abide in an ongoing state of death—when it comes to selfishness, grasping, treachery, lust, hypocrisy, pride, and insolence, we consistently run a surplus. But in the death of Jesus that way of death was gloriously put to death. This is why Jesus said that when he was lifted up on the cross, he would draw all men to himself. In the kindness of God, the Cross is an object of inexorable fascination to us. When men and women look to him in his death, they come to life in his resurrection. And that is good for the world.