As interesting as the discussion should be to some of us, to say that manufacturers consider their ECU programs "proprietary" is ludicrous.
If the "black box' is designed to compensate for various conditions, how can this self-regulating system be proprietary? It's still 1's and 0's, and oh by the way, what does Bosch have to say about their O2 signals getting pirated? The list of stolen signals could go on for ever.
And what about OBD-1 and 2? That program belongs to "We the People" since it is our government who mandated it.
No, the real discussion is somewhat different and has engine shut down technology mandated in all vehicles, with Law Enforcement being the only entity with access to it. Or the technology that automatically limits your top speed to XXX MPH on certain sections of highway, or a myriad other ways to control your vehicle remotely.
It's easy enough to get us gearheads to stop messing with it. Just look at California for inspiration. With it's SMOG inspections, don't even think about touching your vehicle. Or Reno, or Phoenix, and the list goes on. We're already half way there.