In a free market, profit isn't determined by cost or your intuition about "fairness". Price is determined by supply and demand, and profit is price minus cost.
Foxxconn already pays well above average wages while providing a safer workplace than the average US manufacturer, and a lower suicide rate than the Chinese average. And this is still going up even as working hours decrease.
Whether all these criticisms are completely legitimate or not (for example I think workers should be allowed to work more overtime if they voluntarily choose to, to get more money, instead of being capped at 49hours/week), Apple is responding to them as well as anyone could ask for.
Apple's competitors are not getting the same scrutiny. Since Apple is handling the issue great, isn't there room for some of that attention to land on others with much worse practices?
Further, Apple has nowhere near 80% of the production or employees or anything like that. There are other big players as far as how many Chinese workers they are involved with, which I think is the relevant metric for how important reform is.