[lxgr]

That might work for Ethernet, but how would you do that for any unidirectional USB-C alternate mode without protocol-level feedback such as analog audio or DisplayPort video?

If you want to allow all of

- Reversible connectors

- Passive (except for marking), and as such relatively cheap, adapters and cables

- Not wasting 50% of all pins on a completely symmetric design connected together in the cable or socket

there's no way around having an asymmetrical cable design that lets the host know which signal to output on which pins.

[NetMageSCW]

You do it like Lightning did with a chip that controls the pinout as well as reporting the use case.

[lxgr]

That’s basically how USB-C does it too (except that the chip isn’t strictly necessary; an identifying resistor does the job for legacy adapters and cables).

USB-C was heavily inspired by Lightning.