But the doctrine that we are born imperfect (sinful) is commonplace -- and not just within Christianity. The Hindus teach rebirth after rebirth on a path towards our true and pure spiritual state -- the upshot of which is that we are far from that now. The Buddhist stance that we need enlightenment and that we should strive after right thinking, etc. stands testimony to a view that naturally we are comparatively in the dark and don't even think straight. The Taoist emphasis on the Way makes its own comment about how often we're on the wrong path. Confucius' constant examination of the ideal man, the gentleman or benevolent man, includes a lament that he has never met one. The ever-growing self-help/self-improvement sections of the book stores reflect the widely-held assessment that we are not what we should be. All the religions mentioned here have a teaching of how we are meant to be, what we are meant to become -- and imply how sadly and tragically and even dangerously we are less than that. This is "original sin" in the Orthodox sense, possible in the original sense: being sinful or separated from God.
Want a test for how far off the mark we are?
Love the Lord your God with all your heart, mind, soul, and strength; love your neighbor as yourself."
Did you ever notice that, if this were really the fullness of our desires in life, we would always be glad? When would we ever lack a source of joy if this love filled us? What part would boredom or apathy have in our days? Mediocrity, pettiness, loneliness and futility would be banished. Would we even recognize our lives if it were characterized by a deep-rooted love of all around us?
I would not comment on "original sin" to make anyone feel bad about how they are. On a basic level, people recognize the fact of being less than we were meant to be.
To think that this is actually how God intended us strays dangerously close to blasphemy against the creator. The "total depravity" doctrine of some circles is an acknowledgment of how low mankind can and will sink when it turns wholeheartedly away from God. An honest and humble survey of every life I know shows not just the scars of sins done by others, but the shame of those we ourselves have done to the harm of others. Rightly taught, "original sin" gives genuine hope that this is not all there is to humanity, that in the future there will be a restoration. That we hope for something better requires an admission that something is wrong here and now.