Why can't USB Type-C be made as small and thin as Lightning?

USB Type-C is not just an interface specification. The USB3.1 specification was released along with Type-C.

The most direct change of USB3.1 over USB3.0 is that the speed can reach 10Gbps. To achieve this speed, the first thing to solve is the shielding problem. If you look closely at all versions of USB ports, you will see that they are covered with a shell. The role of this shell is not only to fix, but also to shield. The faster the bus speed, the higher the shielding requirements. Therefore, the layers of shells outside Type-C are mainly used to shield interference.

The following figure is a reference diagram given in the Type-C specification. The thing in the middle is used to transmit data, and the things outside are shielded:

There is no shielding layer outside the lightning interface, and the connector alone is not enough, so the speed of the traditional lightning interface can only reach the level of USB2.0.

Note: This refers to the conclusion drawn according to the earliest official lightning interface definition, because the lightning interface has only 8 contacts, except for power supply and GND, the remaining contacts are not enough to support USB3.0. The pin definition of lightning to USB3.0 is not found on the Internet, only the USB2.0 version:

Size and plug-in convenience are secondary. The first problem to be solved is to ensure reliable transmission of 10Gbps signals without interference. In fact, it is not impossible to remove the outer shell, but the speed must be reduced. I don’t know how much it will be reduced. Anyway, I have seen in the USB2.0 era that after removing the shield of the connector, the speed of USB2.0 directly dropped to the level of USB1.1.

It is really difficult to achieve both high speed and small size. One side must make some sacrifices.

Supplement: Regarding the speed of lightning, the highest speed that can be found is 12Gbps, but the data source and interface specification are not provided. Although iPad pro has a lightning to USB3 cable, the lightning interface speed of most Apple devices is still USB2.0, while there are many type-c USB3.0 devices on the Android platform. This at least shows that it is difficult to increase the speed of the lightning interface, at least not as easy as USB.

There is a big difference between running at a high speed in the laboratory and running at a high speed with cheap products produced by ordinary manufacturers. USB Type-C provides a cheap high-speed interface solution, which is exactly what the lightning interface does not have.