Dan H. brings up a point that raises a big question (which I’ve emboldened) in response to Original Sin: Jesus’ Ambivalence:

Hmm. I would agree that Jesus never articulates an Augustinian
understanding of ‘original sin’. But I would also agree with some other
commenters that the passage in John 9 does not really address the
question one way or the other. The question: ‘do bad things happen to
us because of our sin, or as a punishment inherited from our ancestors’
sins?’ is different from the question ‘do we have sin woven deeply into
our nature as a result of an initial Fall?’

I will also say, though, that there seems to be a persistent lack of
clarity (in myself as well as others) as to exactly what we mean by
“sin” as distinct from “original sin”. I did read the definition that
Tony posted from the BBC, and it does seem clear that Jesus did not
articulate that specific definition. But I wonder just how much that
specific definition of “original sin” is really crucial to other
aspects of evangelical theology?