Yes, exactly! As usual, he's pontificating based on how it feels to him rather than after having actually examined all of the relevant aspects.
Dominance-based hierarchy, rather than ones of merit or actualization do tend to cause problems, and those are the sort Peterson really loves - where might makes right is seen as an element of "merit" and immutable traits as well as being born into privilege somehow aren't looked at with a critical eye either. I do agree with you that we have many, many examples of large civilizations that eschewed any real hierarchy or where kings or chiefs had almost no actual power.
I appreciate your sensible analysis.