If original sin is the idea that we are all born already sinful, it is a foolish, hurtful, counterproductive idea. At most I would agree we are born with the capacity to sin, to make mistakes. In short, we are not perfect. God in this sense does not save us from sin or original sin. Instead he provides a moral compass to help us know right from wrong and thereby avoid (but not eliminate) mistakes, and to confront the mistakes we do make.
I don't see why belief in original sin is required to be a Christian. I thought a Christian just had to believe in the divinity of Christ, and follow his teachings.