>Pointing in the vague direction of an exemplar system and describing it a positive argument does not constitute an argument.

Neither does saying "hierarchies do not scale well", or "no they don't", without providing any evidence. So at least you are both "arguing" on the same level: unsubstantiated opinion.

Pretty much every large business and government is also explicitly hierarchical. For a particular firm it's such a common choice one has to imagine it's a good one. For organizations or broader scope than a single firm (industries and economies, cities and nations) independent competition and cooperation seems to work quite well.