There's opportunity for nuance in these concepts. World citizenship needn't mean the elimination of any other hierarchy of rule and representation, in the same

There's opportunity for nuance in these concepts. World citizenship needn't mean the elimination of any other hierarchy of rule and representation, in the same sense that the existence of the US Federal government doesn't eliminate state law, nor the EU government negate individual nations. There exist some entities like this already, like the International Court of Justice (although admittedly weakened by being beholden to countries signing on). However, your point in that most folks that use the phrase "citizen of the world" are likely to be more politically progressive writ large than the median person strikes me as likely to be true.