The author, Dean Schulz, an engineer with a PhD in computer science, takes a “bottom up” approach.
The “hierarchy” that Dawkins is referring to in the video is the tree of life that evolutionary biologists can generate.
Whether their question was chosen intentionally to inflate the degree of support for “evolution,” I cannot say.
Harari’s conjecture — “There are no gods” — forms the very basis for everything he says in the rest of the book.
I am not of the opinion that we should speak only good of the dead. The passing of a public figure is a good time to consider his impact.