The fundamental thrust of the article is that poor countries only "converged" for a short while due to the Chinese-driven commodity boom, and I think this argument is very compelling. Worse, as history has shown tons of times, commodity booms often end up being bad for a country in the long term because they don't lead to meaningful investments in other productivity-improving endeavors (e.g. Dutch disease that the article mentions).
And I think a subtext of this article is that the economic profession in general has a ton of soul searching to do. Too often economics has depicted rosy outcomes for a host of activities where it has just been flat out wrong. This article goes into detail about how "convergence" almost never happened except for a short "sugar high" driven my Chinese commodity demand. Similarly, I've seen a few mea culpas over the years arguing that the once orthodox view that globalization would be great for everyone failed to take into account how it could contribute to destabilizing democracies as the "economic losers" in rich countries started to demand more political power, one aspect in the rise of populism and some of its dangerous effects.