Is it inconsistent to believe that the world is totally unjust and, yet, also believe that individuals who put forth more effort are generally more successful? I think not.
The world itself may be totally unjust; physics shows no partiality for individuals who possess a greater "morality" or work ethic. However, we do not only live within the world. We also live within various frameworks, such as a culture, society, company, etc. These frameworks are not governed merely by physics, but by other humans. And these other humans do, almost by definition, show partiality. Therefore, I argue, that you can increase your chances for success through your own actions. This is not inconsistent with claiming Pol Pot and torturous jihadists "won"; they could have simply assessed their situation and, by their own effort, maximized their chances for success.
You want to believe, I dare say, maybe because of all the hard shit you had to go through. But there is somewhere in Aleppo or elsewhere someone who went through all the same hardship as you, and worked hard, and was nice and all, but who died miserably after having being tortured by jihadists or whatever and having seen his whole family beheaded. In fact, there are millions upon millions of people that did everything right but were unlucky to be born in Uganda or Syria or Libya or Bangladesh, and got fucked in the end, like most of the thousands who were drowned in the Mediterranean last year. Luck trumps merit. That's the whole point of the original article.