Agreed, I found that writing also chose to use quite manipulative, or even emotional language to subtly get the lean towards the author's way. Which is completely fine if the book were presented as "Here's just my opinion on what may have happened", rather than presenting it as "Scientific history of mankind" - this aspect is what bothered me the most.

But we suppose the group who would fall for this kind of strategy is the exact audience the author was going for.