Hitchens makes 2 or 3 mistakes. He takes a totally legalistic point of view, He seems to ignore that when we started as a race that we were in communion with God...
If that was brought to an end for everyone because of the actions of two people (or whatever they represent), that makes god unjust and unfair.
He seems to ignore the new testament declaration that Christ has overturned the work of Adam.
Which is where we run in to an even more bizarre parody of justice in the bloodthirsty, sadomasochistic, incarnation, tortured to death, and magicked back to life nonsense.
There also seems to be the suggestion that God has trapped humanity, that he is a cosmic dictator and that you can only be redeemed or otherwise because of what you intellectually assent to.
In terms of mainstream christianity, original sin only comes in with Augustine and the augustinian understanding is not universal anyway.
However you dress it up, most versions of Christianity claim that we are all sinners, which directly corresponds to being created sick and then being condemned for it, unless we swallow the absurd nonsense about Jesus.
If
everybody sins, that isn't a choice, it's a design flaw.
Mainstream christianity states that relationship with God is available through Jesus Christ.
But only if you're prepared to accept this bizarre nonsense and its monstrous god.