I'm not a professional reviewer but if I don't like something I sometimes make my mind known and gives low rating with what I and many others that liked my review think was an accurate description of the story. I explained the reasons of giving low rating like plot holes, inconsistencies, bad usage of genders terms, personal opinions on bad plot twists instead of spamming words. And some people seems to agreed with my reviews. But so what? I just received notification that my review(s) had been removed by author(s).
It's like if the sellers in Amazon are allowed to give rating and reviews of their own product while removing all the bad reviews.
I agree that novels receiving low rating spams are victims and they somehow need a way to remove the spams, but it shouldn't be authors' authority to removed them. If the reason of giving Authors this authority is the lack of manpower can't they just create or use a function or program to automatically detect spams and remove them? It shouldn't be that hard as spams usually have the same wording or patterns. Even the spammers usually have similar usernames.