Let's assume first that is true.
And these articles are about Go being Google's language, which is empirically and legally true.
Different from C. I can write a C compiler with extensions and release it, call it C or "Something-C" and no IP problems. I can even call it Standard C and even if it's not no one can do anything. I maybe can't call it ANSI C if it's not standard compliant, but that's because ANSI is a protected term, not C. And unlike Go.
Now let's assume it's not true.
In that case Go is not Google's language and there are no ip issues. I can make and release a compiler, call it a Go compiler, and I'm fine.
Which is it? Unsure. I find no information suggesting Go is trademarked. But there are people like in your post claiming that it is. If so that should be easy to cite. I really don't know which it is. So many people claiming the word Go is protected. Perhaps they have better references than I could find and we can figure out what sort of language Go really is.