It seems to me to be the product of a worldview which sees children not as distinctive individuals with unique preferences and aptitudes, but as mere larvae pas

It seems to me to be the product of a worldview which sees children not as distinctive individuals with unique preferences and aptitudes, but as mere larvae passing through 'developmental stages'. I consider it an affront to the dignity of all children and my teeth are set on edge every time I hear it. For outliers, statistics doesn't work that well (and feels reductive of their uniqueness.... because it is!). And of course this is true of everyone - we're all unique and special and statistics doesn't get to the heart of our own personal story. But this isn't the point of such things - terms such as age-appropriate are really aimed only at most children, most of the time. Anyone who's enough of an outlier to be offended and upset by the notion - and able to come up with a cogent argument against it - is probably not included within that set of most children.