The European Union agreement requires all chargeable battery devices, including smartphones, to have USB Type-C as a “common charging port” by Autumn 2024.
USB-C benefits
If iPhones get USB-C, Apple users will be able to use a single cable to charge all their devices like Mac, iPhone, and iPad.
Why Apple uses Lightning cable?
The sole reason Apple stayed with the Lightning cable is that switching to USB-C would result in a lot of e-waste and loss of control over what peripheral gets attached to an iPhone.
Expected transition to USB-C - According to rumors, Apple will switch to USB-C with iPhone 15 in 2023.