The word sin and the word unconscious are both but words. We can mean different things when we talk about sins and unconsciousness but I would say that it is the same thing.
In biblical Hebrew, the generic word for sin is het. It means to error, to miss the mark. It does not mean to do evil. (Wikipedia)
In Buddhism and Hinduism, they do not talk about sins. They talk about Karma. Good deeds produce good results bad deeds produce bad results.
Atheists do not use the word sin. They talk about right or wrong. It is wrong to abuse children. It is wrong to exploit poor people. You use the word unconscious. Only unconscious people exploit poor people or abuse children. It is a matter of words. If the bad deed is wrong, bad karma, unconscious or sinful doesn’t really matter, I think.
The belief that awakening is possible to all people, also to those who have done terrible things is not cynical. We have all been unconscious and we have all done bad things. I also believe that awakening is not about an on or off kind of thing. You can wake up to some extent during the day, some days more, some days less. One moment unconscious, the next moment half awake, sometimes wide awake. Enlightenment, the final awakening is for the Buddhas, I think, not for me. Soon we will disappear in the fog of Alzheimer’s disease or some other form of dementia.