I think the Book of Genesis conflates a lot of ideas into a very simple story. It would be virtually impossible to get everyone to agree on when it was written, who wrote it, and what it tries to convey. Most skeptics still claim that the Hebrew Bible was written during the Babylonian Exile. Recent research
shows that some Biblical writings were fully formed centuries earlier.
The dating of the Biblical writings is important because knowing WHEN they were composed and WHO composed them would help us understand WHAT they were intended to teach. You have to strip away the centuries of commentary and interpretation that have accrued to understand what was originally the intent of those stories.
Modern "fundamentalists" and "skeptics" alike rely on fairly well established bodies of opinion to explain the Bible. Both groups are biased and omit relevant information. For example, some teachings or interpretations have been well preserved from ancient times. Scholars can study what their ancient predecessors taught about the Biblical texts. But today many religious and areligious scholars and experts draw upon modern opinions and interpretations to frame their own commentaries.
It's just a very confusing discussion comprised of a million arguing voices.