Inequality is correlated with all sorts of bad things (at least if you look at subsets of the international data, which often includes different countries and time periods and doesn't control for outliers, mediators, moderators, and confounding variables). But we all know correlation is not causation (even if we're looking at good, truly comparable data).
Did you know that in the US, increasing inequality is correlated with decreasing crime rates? Or that, internationally, divorce and suicide rates are higher in more equal societies? Check out these charts:
No - I'm not saying inequality is a good thing. Nor am I saying that graphs lie. The above graphs reflect accurate data. The point is that correlation is not causation - and this principle applies whether or not you're sympathetic to the point.