Sometimes a game doesn't need every element to be at the height in a person's mind. To me games aren't a sum of graphics, technical prowess or it's story. It's the experience I had with it.
MGSV was a terribly flawed game that I didn't actually finish. But it was one of my favorite games of that year because of how much fun I had playing it when I did. It's mix of systems and gameplay are at the top of my personal list.
I get not everyone wants to buy into the hype and assume the reviewers have some extreme bias, that's your right. But to be incredulous because it's not the perfect game in your eyes is also a bias. Maybe it doesn't "innovate" on any one idea but the mix of those ideas, how they are put together and presented, goes a long way.
I don't care at all what it's cumulative rating is but based on what I've read so far I'm incredibly excited to have this experience myself.