Sure: "40 hours a week" for moderns is also an underestimate.* But the figure everyone goes around repeating about hunter-gatherers is a more dramatic underestimate. The accurate !Kung estimate is 48-56 hours spent on these things: so we seem to be about the same, but with massively improved quality, cost, and nutrition for us.

The debunking applies to the claim that they had more leisure than us. Lee says: "work week... of 2.4 days per adult... [the bushmen] appeared to enjoy more leisure time than the members of many agricultural and industrial societies."

* Industrialised-world cooking time per week seems to be about 6 hours. https://www.statista.com/statistics/420719/time-spent-cookin... Difficult to find average shopping time, but call it 5-7 hours a week. https://www.statista.com/statistics/521924/time-spent-househ...