Comment by NelsonMinar

This reminds me ChromeOS has some USB-C cable identification superpowers: https://www.reddit.com/r/UsbCHardware/comments/1pyojjd/comme...

Not sure if it's using the same thing this MacOS thing is doing. In the link the author explains that the cable e-Marker contains a "Discover Identity" message that you can read and display in ChromeOS. Most ordinary Windows hardware can't read it because of BIOS limitations, but Chromebooks can. I'm guessing Macs can too.