Why does a close examination of the doctrine of Original Sin matter? Because it is the “foundation” upon which much other Western doctrine is based. Scott M, take it away:

Hmmm. Part of the problem may be that we
have fixed names for these characters, ‘Adam’ and ‘Eve’. In truth, if
it is used as a proper name, ‘Adam’ is not so used until Chapter 4.
Before then, the references are to ‘ha-adam’. (Pardon me for any
inaccuracies. I’m hardly a language expert.) The ‘little ground'(?) and
elsewhere the man and the woman. We also totally miss in translation
the play on words.

I’ve never found it particularly important to the story whether or
not there were two specific people involved. By the time we start
getting a family narrative in Chapter 4, we see when Cain is exiled
that there seem to be plenty of others outside his family for him to be
worried about. Chapters two and three have a pretty different feel to
them. And referencing ‘the man’ and ‘the woman’ fairly generically
seems to me a good stand-in for referencing humanity. (In that sense, I
do think it is paradigmatic, though probably not the word I would
choose.)

However, we are born into a world which has been damaged by eikons
of the Creator reflecting other than that Creator into it and by eikons
trying to become the eikon of something else. In that sense, we inherit
the consequences of sin. However, just as the Resurrection is not
merely some historical event (though it must be that), but indeed the
center of reality — including time, so too I don’t see ‘sin’ as a
purely linear, historical progression. We do not just affect ourselves
with our ‘sin’ or those we directly touch. Rather, in ways we do not
see we affect all reality, of necessity including time. So we are born
‘in Adam’ and indeed inevitably participate with Adam. In that sense,
we are all Adam. Nothing less seems to make sense of either Scripture
or Jesus to me. So to say that creation is affected by our sin does not
to me imply a time when it was not so affected simply because we did
not yet exist in a linear progression of time.

I think there are many problems with the Western doctrine of
original sin. But not least among those problems is the fact that it
effectively trivializes the true problem. I think that’s why the
Resurrection has, for the last thousand years in the West, become
increasingly adjunct, often little more than a add-on, and from there a
short step to unnecessary. I saw that very clearly a few years ago
reading an SBC publication (the denomination to which I suppose I
‘belong’). There were a lot of articles talking about and defending the
Resurrection. But when it came to describing the ‘why’ or what it
meant, the most they could say was that it ‘proved the Father had
accepted the payment of the Son.’ I was stunned. I suppose I still am.

As I’ve tried to say, there’s a lot more at stake in how you view
this question than is immediately evident. It sends shoots everywhere.