If anyone has leverage, its Apple, so actually yes its a way to start fixing the problem.
There's a simple way to keep slave labor out of your supply chain, stop doing business with people who are fine with that, not "performing audits to find out they are using slave labor again so we switched!"
No, that’s a convenient misdirection to avoid real change. By making it “Apple is evil”, people just switch to another phone manufactured in China and pat themselves on the back for doing absolutely nothing.
Auditing suppliers, verifying supply chains and switching away from cheaters is one way to address the issue. Another is to not do business in China at all.
Maximising downward pressure on wages - as an economist might label this - is the natural, predictable, desired outcome of globalisation.
The fact is you can't buy a single thing made in China and be sure it isn't implicated in this in some way. Think of the last few things you bought that were manufactured or sourced some parts in China. Can you honestly say the manufacturer audits their supply chain with the same rigour? At least Apple is trying to keep their supply chain clean, but ultimately that may prove to be impossible.
If that's the case vilifying Apple for it won't fix it, the only way to fix it will be to shun Chinese products completely, but that's going to be a very painful and difficult process for more people than just Apple. Take Fairphone for example, those guys work really hard to do the right thing as much as possible, but they have dozens and dozens of suppliers in China some of them indirect. In their own literature they point out they can't answer for every single supplier. This is a really tough problem.