Now, I’m not asking companies to open-source their entire codebase. That’s unrealistic when an app is tied to a larger platform. What I am asking for: publish a basic GitHub repo with the hardware specs and connection protocols. Let the community build their own apps on top of it.

I agree with this. I think the most important thing is not necessarily the original company releasing the code (although that would be nice), but it being easy (and legal!) for hackers to reverse engineer and/or build on top of the platform.

The irony is that, since most such products will have some GPL’d code in there somewhere, most products already basically have such a requirement, thanks to the section requiring complete corresponding source including installation instructions. Hopefully, the Vizio case will establish the precedent that users can take action against such companies.