Yes, that is what it says. Not "cannot be used in court". Just that they consider the English version authoritative.
Are you trying to tell me you can't tell the difference between these statements?
Are you trying to tell me you can't tell the difference between these statements?
It's at least no more of a leap than telling someone they're lying when they're paraphrasing, and in a way many people think is fairly accurate.
Did you think that an eyewitness account of a murder would be inadmissible because it's not a legal document?
You can use an empty soda can in court. The FSF probably hopes that they are used in court as a starting point.