The argument is an interesting one--the more complex the metric, the harder it is to act on it--but the author provides no reason for this other than his graphs

The argument is an interesting one--the more complex the metric, the harder it is to act on it--but the author provides no reason for this other than his graphs, which are representations of...nothing? Simply drawing a line to represent his thesis doesn't mean his thesis is based on data; it just means he knows how to graphically represent his thesis.