https://github.com/Konik-ai/j1939_dbc/blob/main/dbc/j1939.db...
There are a ton of dbc files floating around like this. Almost any car with a turbo has a kit to flash the ecu for more boost, so even the proprietary signals have been reversed.
Ghidra exists. That doesn't mean all software is open source.
> You want to force companies to publish and maintain repositories using your preferred toolset?
Nope. Anywhere will do, whatever is easiest for them, as long as device owners can access it.