[wkat4242]

Only if all those iphone users use this feature all the time, and only if before enabling this they always happened to charge when clean energy wasn't available. This calculation is very optimistic.

Often people need a phone charged asap so this won't work.

If they actually make iphones more repairable and last longer so they don't have to waste natural resources to make new ones, it would have a far larger impact. But hey then they'd be making a little bit less profit.