There is no evidence that Apple ever planned to introduce a MFi system with USB-C. What likely happened is that leakers misinterpreted the USB-C E-Marker as a MFi chip.
Or that Apple was considering a "made for iPhone" certification program to allow manufacturers of USB-C devices to certify that they'll work with iOS devices -- which would be a perfectly reasonable thing for them to have! -- and misinterpreted that as meaning that Apple intended to implement a restrictive device authorization scheme like they had for Lightning devices.
(Just because newer iOS devices have a USB-C port doesn't mean that all USB-C devices will work with them! Devices still require drivers; if iOS doesn't know how to handle a device, it won't work.)
