Not my call, but hard to argue that the 0.5 is a legitimate review. Surprised it survived.
One distinction in the Beaver Ranch vendettas was that it appeared to be an organized assault on the course's reputation, with multiple attack reviews. A little different than a couple of hits, among almost 100 glowing reviews.
It certainly doesn't affect the rating itself very much. Is anyone saying, "I'm not going to play that course because it's only 4.67. Now, if it were 4.74, I'd change my travel plans"? Or reading all those reviews and thinking, "Boy, all these people are nuts, but this guy who doesn't like the cost is right. I'm not playing there"?
It's only the obsession with the Top 10 list that makes it matter, at all. But it's never going to conform to everyone's tastes; there will always be some courses on it that something thinks shouldn't be, and vice versa.