That was David’s lament, not God’s word. Several translations and interpretations are available.
It is almost universally accepted that it does not mean the unborn are sinners.
no sorry, it’s not ‘almost universally accepted’, it’s only accepted by those who reject original sin being passed down- many folks do not believe that way-
If you meant ‘almost universally accepted’ by a certain religious denomination- then ok-
So, you are saying that Psalm 51 is not God's Word? If not, then how do you define what IS God's Word?