No, it doesn't help, because it's probably unreasonable to believe that Apple would recoup enough of those gains to counteract the losses they suffer from losing their competitive advantage.
It's like telling US Sugar that it'd be a net gain for them to lose their tariff protections.
That some global optimizations with direct negative effects on a particular business outweigh their downstream positives for that business doesn't mean they all do. Perhaps this is more like Wal-Mart lobbying for higher minimum wage so that its customers have more money [1].
Walmart was paying above minimum wage when they lobbied for that change. They were in favor of the wage rise because it would harm their competitors - and give them positive PR as most of their critics were unaware that Walmart paid above minimum wage.
The CEO certainly says he pays more than minimum wage (when the statement was clarified, it turns out it doesn't include part time labor or contract labor, so it's not clear how true that actually is). But why would he pay more than his competitors? (I can find no evidence that it does and a fair amount of evidence that it doesn't.) And paying above minimum wage does not remove the labor market pressure that comes from increasing it.
All that aside, you may be right that it was a chiefly PR stunt and perhaps Walmart is in fact a poor example.
I'd venture that most well run and dominant companies pay more than their competitors. This is likely (speculation ahead) because these companies know that they must obtain and retain higher quality employees than do their competition.
Even for Walmart, their employees are the most important asset. From top to bottom. People like you and me (I'm assuming you've never worked there - I haven't) aren't aware, but supposedly Walmart really does treat their workers well. All in relative terms of course... And based upon pure hearsay of course.
Finally, regarding whether or not it was a publicity stunt: Maybe I'm jaded, but I consider everything that a corporate employee says publicly and in official capacity to be a publicity stunt, almost by definition.
It's like telling US Sugar that it'd be a net gain for them to lose their tariff protections.