I don't think it's that easy. My book on Amazon currently has one 5-star review that's just one word and two 5-star reviews with two words each. I am the author and the publisher, and I know for a fact that these reviews are not fake. But they probably come across as fake. I think that there some people who just want to share their opinion of a book without making an effort to write a good review.

Personally, I'd prefer to have only reviews backed up with an explanation. If a book is good, tell me why. If it isn't good, I'd like to know why you think it isn't. That's the only way to make the next edition better.