No one is arguing that you absolutely can't use Go to build a robot, just that it's probably not a good idea.

Just because someone uses Node.js to build a hobby robot, doesn't mean that many people are using it for production embedded systems. If your systems has hard real time requirements, which many systems do (even many hobby robots), a stop the world garbage collector is out of the question.

Let's say you have a legged robot that depends on interpreting sensor feedback to keep from failing over. What happens to your balance when the garbage collector pauses your code for 10ms?