If Apple switches to USB-C on iPhone, no big deal as port-less iPhone version is not that far in future. Moreover, we all have enough power adapters and USB-C cables lying around in house so all good with USB-C port iPhone. We need to put aside debate of keeping lightening vs switching to usb-c. The debate should be, IS current version(and upcoming improvement) of usb-c better in dimension, versality, safety, reliability, speed, protocol, power consumption, etc than lightening ? I buy iPhone for iPhone hardware, IOS functionality, security and privacy, vetted Apps, vertical integration and not if it has lightening or usb-c port.
edited May 15