Evolution of God.

[deacon blues]

One thing that separates most of Christianity from Mormonism is what the view of what the ancients believed about God. A Christian believing in the Bible could say that early people knew something about God. But God left most of them free to imagine or conceive the incredible variety of ancient and folk religions that study of history and archeology reveals to us today. Christians would say that God revealed his will to the Israelites, and later more specifically and clearly through Jesus Christ. Bur most of humanity was left to develop what we see from today's perspective: early polytheism in countless forms, evolving generally but not always to Monotheism in the modern age.
Informed Mormons would say God revealed much, perhaps most of the gospel to Adam, his descendants for several generations down to Noah, Enoch, Jared's brother, Abraham, Moses, Nephi, etc. Adam/Eve and Noah would be real theological bottlenecks. Teachings about God, baptism, etc., even temple ordinances, according to Pres. Nelson, would be the primary, if not the only religious teachings of the human race for generations.
How can a TBM explain the explosion of religious beliefs that evolved from that single thread of the gospel taught by Adam and Noah?
The disappearance of the LDS gospel is even harder for a TBM to explain than the disappearance of Lehite DNA.

[moksha]

How can a TBM explain the explosion of religious beliefs that evolved from that single thread of the gospel taught by Adam and Noah?

Perhaps they could use the Mormon idea of humans descending from Pre-Adamites and Adamites. The Pre-Adamites had over two hundred thousand years of development before the Mormon Adamites even appeared in Missouri.

[alas]

There you go again, trying to apply logic to religion.

[moksha]

Ents could help guard the forests from Celestial Mormons.

[Hagoth]

Whenever people are capable of stepping just a little bit outside of their immediate mindset, the first thing they should consider is why they just happened to be born into the "true" religion, and why everyone else also believes they belong to the "true" religion, even they are unquestionably part of a false religion. The obvious answer is:

God seems not to care that much, and just allows the most geographically convenient religion to be the true one for each of. If God either doesn't care to bring us all together under one roof, or isn't capable of doing so, maybe we shouldn't care either. We can even turn a religious trope around on them: I guess you think you know better than God!?

Bonus points: can you even find the one-and-only-true-religion that you just happened to be born into on this map of the entire freakin' religious world? It's claims to be about the same size as Judaism, but doesn't even rate a star.