There's a strain of Marxism called Maoism Third-Worldism. (This relates to the article -- I'm getting to it.)
This is a contentious strain within Marxism because of the way it contorts some of Marxism's basic ideas to its own ends. The main one being Lenin's theory of "labor aristocracy." If you're not familiar with this, it's the idea that the working class in first world countries is effectively "bribed" by their national bourgeoisie through wages higher than those available for the same types of jobs in developed countries.
Maoism Third-Worldism extends this concept by claiming that, actually, first world laborers are not exploited _at all_. No matter how bad workers in developed countries have it, their class interests are fused with those of the national bourgeoisie and their share of imperial "superprofits" means that they effectively belong to the same class category as the latter. I'm simplifying somewhat, but this is the basic idea, and it's proven through hundreds and hundreds of spreadsheets. If you leaf through a book like Zac Cope's Divided World, Divided Class, half the book is citations, charts, and tables.
Now I admit I am a bit of a dilettante here, but to my knowledge there have been no serious attempts made to challenge the vast quantitative efforts made by Third-Worldist writers. This is at least partially explained by the fact that Marxist audiences tend to be a bit less quant-focused than their peers in mainstream economics (to put it lightly). Still, it upends some of the most basic contentions of Marxist analysis, so you'd expect there to be a more lively debate over all those charts and graphs. Right?
I claim there's a larger issue at play here: most people are driven to ideas within social sciences for basically pathological reasons. The ideas agree with them on some basic level, and the research is largely a pretext for legitimizing those ideas or creating a sort of ideological playing field for its adherents. People aren't drawn to Marxism or any of its sub-sub-ideologies because they started reading Capital on whim one day and found its ground-up arguments on the commodity form compelling, any more than libertarians start from a blank slate and are "woken up" by reading Hayek cover-to-cover.
So if you propose a wildly heterodox idea within one of these fields, no amount of math is going to help you. Most people, even academics within the same area of research, will either be drawn the idea - in which case, great, there's math to "back it up" - or repelled by it and dismiss it out of hand.
I'll show my hand here by saying the author's idea sounded kind of dumb to me so I didn't look at the spreadsheets.