I'm not sure this is the right place to post about this but I think considering it's a flaw in the rating system this should do.
While looking at the reviews of the fanfiction linked below, I saw someone (user EnumaElish) leaving at least a dozen 1 star reviews making the rating of the story go from 4 something to 2.7. I feel that being able to post this many reviews and "tanking the ratings" of a story is very detrimental to the author and potential readers.
Maybe there should be some limit to the amount of ratings one can make on a single story or maybe a time constraint so that the system is not abused.
Link to the story:
https://www.webnovel.com/book/11512864606403605/Reincarnation-in-Naruto%3A-Konoha's-Genius-of-the-Ice-Style