Just as I remember being wrong about the Book of Mormon populations explaining all of the New World, I distinctly remember being wrong about the Bible and its explanation of the entire world. My current understanding is rooted in much more evidence, and complicated by numerous issues, but the Bible is still and ancient text, and still has a message for me, despite its contradictions. With the Book of Mormon, the situation is even more complicated. The issue of the knowable becomes critical for relating the Book of Mormon to anything found in the dirt in the New World. To describe the problem of archaeology of a religious group, imagine this scenario.
Some cataclysm buries any one of our cities.
All of our books rot away, and maybe no one can read our language for years. We would cook with very similar metal pots. The problem with archaeology is that we have some problems with identification from time to time. Biblical archaeology has some of the very same problems. Even though we know where Jerusalem has been for a while, there is no pottery tradition that marks Israel from its neighbors.