Agreed.
Lightening was most likely a combination of:
* The connection interface was superior to USB-A Micro/Mini in both size and reliability - and this was the contemporary connector in 2012.
* They had undergone a physical connector change only once, and it was not received well by vendors.
* USB-C was not anywhere near ready for the iPhone 5, and the 40 pin would not do well in that type of device.
* USB-C and Lightening are comparable on size and reliability (saying nothing about speed) - so even after USB- started gaining adoption there was not a strong incentive to switch over. It wasn't superior.
* USB-C charging only would be fine, but people would expect drivers for storage, HDMI, radio docks etc. Easy to undersell this effort in hindsight.
I also doubt that it was a profit motive.
let’s not forget that Apple themselves helped design USB-C and pushed for it to be the standard. I guess they couldn't wait for it to be ready, and given the iPhone 5 came out in 2012 and the first commercially successful USB-C devices came in 2016 I guess they were right.