So they’ve shown they can send light over a cable designed to transfer light.

The impressive thing is of course managing to get one specific photon to one specific location. Still, what benefits does that have over the standard encoding?

I guess this technique might have a lower error rate and higher distance, because it’s binary by nature with no quantization needed. But you don’t need the quantum entanglement part at all for this.

Edit: Reading is hard! This is indeed exciting for security. I wonder how it fairs against a very powerful MitM though.