Reviewers are professionals (typically) who are aiming to provide an objective measurement of a subjective experience. IMO, a professional reviewers opinion matters to me more than most other random people's opinions. However, they are still having a subjective experience so we may not see eye to eye on things. What my preference is, I find a reviewer I generally agree with (my views line up with Dunkey's in just about everything but RPG's) and I look to their reviews as a better barometer for whether or not I'll like the game.
With regards to things like Metacritic, I think when you have an average of 89, or 92, or whatever...at that point, if you don't agree, I think it's wise to admit that you're probably in the minority or biased to some extent. I don't believe in games being overrated on a universal level, at least for the time. The reverse is true as well. A game that scores a 51 metacritic is more likely a bad game and your enjoyment is either an outlier difference or bias (such as an old game you grew up with).
Basically, I don't think that game ratings are completely subjective. However, experiences still vary and a review or multitude of reviews doesn't invalidate your personal and individual feelings about the game. Just don't take that personal feeling and try to make it universal (i.e. underrated, overrated, objectively awful, etc).