Although it would be speculation, I imagine this will be included because USB-C iPads already have this feature. One can charge a range of devices, including o

Although it would be speculation, I imagine this will be included because USB-C iPads already have this feature. One can charge a range of devices, including other iPads from a USB-C iPad. One can even change the charge direction between the two devices. Charging on these devices is independent from data access. The user is prompted to allow data access which requires authorisation.