And that’s only, like, the most basic part of an industrial e-stop. On top of directly disconnecting the energy source, it also has to include redundant circuits (since it’s possible for a contactor to break and fail open, or weld and fail closed), and some even need to have signal pulses constantly going through them to actively confirm they haven’t been pressed. They absolutely should not just send a signal to a Linux computer, because general-purpose operating systems are too complex to be rated for safety.

This isn’t even my area of expertise yet I know this stuff. The fact that they failed at the very first requirement is really messed up.