I didn't make my comment in a vacuum. Look at the context. Notice we aren't talking about rape, or financial ponzi schemes. Context clues people, context clues.
I think the prevailing attitude is more like, "Yes, crime is a function of inequality, but it's also a function of X, Y, Z other things, and leaving them out does more harm than good to the discourse."
In an unequal society the crime could just be in the areas of high poverty because the government chooses to avoid improving those areas. Off the top of my head that's just one way to interpret "Crime is a function of inequality."
I can't read that paywalled article, but from the sounds of the abstract, no methodology is introduced to demonstrate causation. Any correlation that does not in turn show causation is spurious.
Do you have more info? Would be great if you explain how they do demonstrate causality. Not really sure why it is on me to refute a paywalled article that has no indication of being relevant. Please note that the OC who posted the link to the study (and to whom I was responding) specifically said "correlated".