I've recently come across a couple of really fascinating videos on YT. Fascinating as one who was educated as a Calvinist at Capernwray. Note, I don't think this teaching, from the 1980s, still occurs at Capernwray.
The idea of original sin popped up from time to time, and I recently read a comment on a video, which I can not now track down, where a self-proclaimed atheist decried the concept of 'original sin'.
I'm guessing that he objected to Adam's sin (rejection of God), being imputed to all his offspring.
I don't think this is the implication of Adam's error.
The risk of deflecting from godliness is given in Genesis 2:16, etc. So we have a tree that gives A&E the option before them: be with me or be against me. Against is an option, but there is a down-side.
In Genesis 3:4, the serpent gives half of the truth, but fails to say that the knowledge of good and evil: knowledge by participation in the converse of God (evil) cuts one off from life and brings death.
Death arrives not just in Adam and Eve, but in creation. The creation from the word of God is complete, and aligned with his glory. It's a world more than wonderful and God shares it with his creature-in-his-image to be the steward of it and make it the place for human habitation.
The creation is now fatally marred. Sin is in it and the whole is now no longer the thing of total beauty and peace and joy that he made. Horror has stepped in. It cannot be stopped by the creature who introduced it, Adam's very constitution has been marred and the marring continues to all of us. We see it in a degraded and degrading genome, we see it in all human interaction.
We are not alienated from God by Adam's sin in us, but by the effect of Adam's rejection of God in the whole creation wherein he (and his offspring) were to be the image of God, drawing to each other's attention the wonder of the creator's generosity towards us.
Rejection of this places us all in a creation that is no fatally marred, misses the mark, falls short, and we can do nothing but also fall short. One rotten apple makes a barrel of rotten apples.
Nevertheless, the creator does an end run and will remake the creation: Revelation 21 (the New Jerusalem is the church, the bride of Christ).
So in a way, the doctrine of original sin is a great relief, ultimately, because it tells us that this is not who we really were made to be, that sin is unnatural, it is something gone wrong, and has brought from God a salvific response.