I think its great you challenge something. You make good points.

Having said that, that initial post by Barry was more his own reflection on his role as a Scrum Master. As a narrative it made a lot of sense to others and so it made the rounds. The article does not argue a prescriptive model to perform all these stances though. It merely provides a descriptive approach to how Scrum Masters can act, and calls that "stances" (there are many more that might work well too). And sure, no Scrum Master alive can claim to be equally good at all these stances. I suck horribly at some of these. And I can still be a great Scrum Master.

I guess what your post does well is challenge the idea that people should use models as the truth. This too is a model, and its just a way to simplify the world.

That's kinda liberating right :)