I guess it should say “except blue”. I have been around since Anu’s was released and accepted that it makes sense not to be able to pick Anu’s own colour. It isn’t actually a bug - it’s always been that way to my recollection. Just as you can’t pick blue gems for Justice - although it says “a chosen type”.
It has always functioned this way, and this isn’t the first bug report thread about it. It seems it should be easy to change the text to say what it does, but I’m not sure it’s ever been acknowledged as something that would be fixed.
I found a very interesting twam to use ths with, and its quite frustrating not to have this work properly. There is no reason it should not also destroy blue.