Those who believe Jesus was purely human tended to understand the Israelites history and they even accept him as a messiah, but that does not mean they think he was God.
They know the monotheism of Israel does not and cannot evolve from polytheism, because the two are based on radically divergent world-views, radically divergent intuitions about reality.
The monotheism of Israel was not, it could not be the natural outgrowth of the polytheism of an earlier age, it was a radical break with it.
Monotheism was a revolution, not an evolution.
I did write that blog, but I depend on that blog to answer questions?