Let me try. I don’t know, first, if “scientific” is the proper term. None of this is scientific. However, creation of the universe, etc., last week or 6000 years ago requires God to lie, presenting false evidence of history that never happened. Genealogical Adam requires no such false evidence, as it’s not expected to have left any evidence. Thus no deception on God’s part, which is theologically better. We have lots of evidence of the universe’s (etc.) age, but we have and can have no evidence against the creation of two individuals added to an existing population.