AFAIK, in hunter-gatherer sopcities people are divided into two groups: those that can hunt and those who cannot, the latter group including elderly, children, women, and very few other people, e.g. the shaman (this also disproves his point about gender equality, in such socities women are, by necessity, second class). So, it is very hard, esp. for men, to specialize in anything other than hunting, e.g. arts or crafts, unless it brings an immediate utility to the tribe.
Another point is: more people = more brain diversity -> easier for people with interesting ideas to be in the society, the intellectual gene pool, if you will. And an agri lifestyle definitely supports larger tribes.
> in such socities women are, by necessity, second class
Not necessarily. Please take into account that in all but most extreme climates, most of the raw calories in a hunter-gatherer group comes from the gathering part, which is mostly a female activity. The problem with a pure gathering diet is that it tends to be protein and fat deficient, so one strategic contribution of the male hunters is not to keep the bellies full, but the diet balanced. Neolithic farmers discovered the hard way that a belly full of grains still leads you to malnutrition.
The other big strategic contribution of male hunters to their communities is protection. The only way a bunch slow moving, child bearing women can wander safely in the wilderness gathering food and wood is to bring a couple of armed men along. This men were probably too old or too young to join the hunters, but would provide a valuable service in protecting their people of predators (human or otherwise).
Not to imply that women are unable to defend themselves... but Nature does not care about political correctness. Females are more valuable to the reproductive capacity of the tribe, so it makes more sense to have males run higher risks.
Another point is: more people = more brain diversity -> easier for people with interesting ideas to be in the society, the intellectual gene pool, if you will. And an agri lifestyle definitely supports larger tribes.