Ok, so Oracle owns the copyright on the code, but not on the name of the language

Names aren't covered by Copyright law, but by trademark/servicemark law. The latter is consumer protection law. Oracle does own the trademark on Java and the coffee cup logo.

and that's why the judge says it's questionable whether "languages" can be copyrighted?

The judge has said nothing of the kind, much less for the reasons you gave.

The judge simply said there's no precedent either way. "No decision on point that says that computer languages have not been copyrightable."

I didn't mean that Perl is unique in separating (or not separating) grammar from functionality.

I know. I understood your point and I agree with it. Your comment simply raised a interesting question.