I can't find anything about that in the article or the Fairphone 6 manual. Do you have a source for this?

My main problem with USB-C headphones on my Android phone is how unreliable they are. But if the USB-C port can just pass through an analog audio connection, that should work much better, I expect.

Edit: This feature is apparently deprecated (removed?) in newer versions of the USB spec! https://en.wikipedia.org/wiki/USB-C#Analog_Audio_Adapter_Acc...