Go is a systems language. The term isn't confined to device drivers. It includes platform/backend software such as web servers and things like message queues or the Docker ecosystem.
Real time programming requires you to be able to make hard guarantees about how long a certain piece of code can run and what resources it uses.
This is literally impossible with a GC because you can only bound one resource (time or memory) at a time.
The best RTS languages are a pain in the ass to use because the compiler will complain about everysinglething - cases that could go wrong with your code
They are used in mission critical (in all sense of the word) systems like spaceships - where a tiny bit of lag will send it thousands of miles in the wrong direction.
Those links you provided, one is a draft for a spec, it's not even implemented yet - and the other has nothing to do with real time languages.
Maybe it would be easier for both of us if you wrote the definition for real-time or systems programming, rather than just saying something isn't one or the other.
By your argument Ruby and Python are also systems languages because they can be used to write servers and job queues.
You're not doing real time programming with Go. Don't make systems programming lose its meaning by promulgating this myth.