This article is not about averages where outliers drive up the metric (like wealth or income), it is about defined cut points.
I'm still not seeing how that would relate to what he is saying, though. We are talking about the world, and the world getting better, which the data shows it clearly is.
And the "is" is important there, that's the current trend we have.
The world is getting better for some. For others all hope of a future where they ex. have a job is increasingly common. It all really depends on how you measure it.
