It's kind of hard to claim to be doing an "unbiased review" of something, when at the end of the day, you're still just giving your own personal experience of the game, your own personal take, flavored by your own personal tastes and opinions. You may have found the game to not be challenging, as well as "repetitive and uninspiring", but others would likely totally disagree with you, thinking the game was very creative, a lot of fun, etc.
It would have been better to just say "Hey this is my take on the game", instead of trying to put forth the idea that somehow your review isn't just your personal opinions of the game. Everyone is biased, because life is subjective.