The author's argument is that their conception of meritocracy is laudable because it grows the pie, and growing the pie is the most important thing if we are to

The author's argument is that their conception of meritocracy is laudable because it grows the pie, and growing the pie is the most important thing if we are to avoid fighting for scraps. They're not saying that growth and distribution are orthogonal, just that the former leads to a better latter and ought to be prioritized. This is ironic in the sense that much scrap fighting is the result of growth being captured and allocated by meritocratic elements (as defined by the author) in ways that make fighting for scraps more likely, from nobles wasting the surplus on political struggles to the smartest people today redistributing wealth around instead of creating it. Perhaps a more poignant example would be the deterioration of the environment. Peak performers have created much wealth in the past by harnessing fossil fuels, but the negative externalities can now lead to an equal if not worse destruction of wealth in the future. The author's view does not take into account these situations that go beyond the simple struggle between individuals in a historical, physical, and geographical vacuum.