The author here and Pinker are using different definitions of "poverty". The author's definition is defined in terms of wealth inequality. By their definition

The author here and Pinker are using different definitions of "poverty". The author's definition is defined in terms of wealth inequality. By their definition, there is a similar level of poverty today in America as there was in the 1920s. Not an unreasonable position to take, really. But Pinker was talking in terms of absolute material wealth. The percentage of humans going without good nutrition, or any access to medicines, or without access to industrially mass-produced goods like clothing or steel tools, has fallen very sharply since the 1960s. This is such an introductory level distinction understood by nearly everyone that I'm rather surprised someone writing for Jacobin, which while quite far left is usually intellectually rigorous, could fall for it.