It’s a poorly-conceived first thought. How does having the source code protect someone against a tracking bug hidden underneath their car? Is a stalking victim supposed to upload a modified firmware to a computer they don’t have physical access to, and might not even know exists? Or do you figure that giving more power to the person deploying the computer, the perpetrator, is somehow going to help the people they victimize?
I suspect you're over indexing on what what a person being stalked would do with code. The source code is a tool, and it can become clear to people outside of the corporate interests what the security model or lack thereof is.
I'm curious whether you think there is any benefit for tracking technology to be proprietary.