Kinda, yeah. It can be easy to tell when the singer of a Japanese song doesn't really understand it because they kind of feel emotionally lacking a bit. She may have been technically better than the likes of
Bae or
Laplus, for example but I'd say those two sang it better because they understood what they were singing rather than mimicing sounds.
One of the reasons I think Gura gets so many compliments for her Japanese singing is because she is so good at putting emotion into her songs where needed even if she doesn't really understand what she is singing, along with her pronunciations.