Spent 15+ years developing code for medical devices. I doubt very much that opening the source would have much impact on quality.

For starters, without access to the hardware and understanding what it's supposed to be doing, how do you know if the code is right or not?

Let me clarify that I'm not opposed to open sourcing the code, once issues around Trade Secrets are handle. But I don't think it would have even remotely the impact this group believes. The vast majority of device problems I've seen were system issues, not just a coding error.

I don't need to know much about what it's supposed to be doing to critique a data channel that transmits plaintext over a radio, or accepts commands without cryptographically authenticating the sender.

I also don't need to know much about the intended function of the device to find coding styles that cause problems in an embedded environments.