I didn't read the article, just the quotation, but it looks like what they might have done is not mention any kind of libertarian principles. I think lots of people have known about this problem for years, but it is a problem that is at its worst in the US and doesn't seem to ruin as many lives in countries that people perceive to be more heavily regulated. Norway did a remarkable job of not letting oil companies dictate terms to it, while the US let's large companies basically write their own laws.
The problem isn't that government is bad, the problem is that when a small number of people control too much wealth, they will control the society whether it is ostensibly a democracy, a dictatorship, a monarchy, a libertarian paradise, or a hippie commune.
And the simple fact that rich people get what they want is why this position hasn't been taken seriously from libertarians. It's because the libertarian ideal doesn't include controls to ensure that individuals or small collectives can't amass wealth and take over society so a society built on the principle of liberty and minimal regulation will (in the belief of non-libertarians) simply devolve into the same state, with a few powerful rich people dictating terms to everyone else. In anarchy this is done with guns, in democracy it is done with lobbying, in a libertarian society it seems like it would be done with lawyers (more money to hire better lawyers means never having to keep your contracts and being able to force others to keep theirs, for example).
This article just explains one of the mechanisms through which money buys power even in absence of corruption. There are many. But you can't solve that problem by removing government, because money buys power in every single other sphere, and government is one of the very few things that can actually stop the money/power from being accumulated in the first place.