What Are The Problems With The Apple Lightening?

Apple has used the lightning connector for seven years.
It used to be on everything, but now it's only found on two types of devices — iPhones and some iPad models.
The lightning cable Apple includes with the iPhone doesn't support fast charging and transfers data at USB 2.0 speeds.
Switching the iPhone to USB-C could unify Apple's products.
1. It's proprietary - so fewer devices can use it.
2. It's more expensive.
3. It's slower.
4. It doesn't support fast-charging.