This article sums it up rather well: http://www.theverge.com/circuitbrea.../apple-uac-usb-c-iphone-lightning-replacementI put this rumor at 50/50. Either they will or they won't. But your argument against it... it fails. Yup, there are tons of devices that use lightning. After the into of USB-C, those devices will still be able to use lightning. It was the same when Apple converted from 30 pin. People survived and adapted then, they will do the same now. We don't know if there will be benefits over lightning. Depends on what Apple does with their USB-C implementation. Catching fire with 50 cent USB-C cables? You mean like with the 50 cent lightning cables hanging on a rack in every gas station across the country?Apple can also offer MFi certification on USB-C cables. Not an issue.
Chances are <1%. The iPhone 7 and Apple Watch are our best insights into their plans. Less connectors, more wireless data transfer, wireless charging. Not swapping out a good connection for a more risky one.