The problem is that it can't really be judged as a complete game. Like what a review is supposed to do.
It's unfinished. Regardless of what the game assets show, third chapter or not, it doesn't matter.
The story is lopsided because there's a third of the game missing. The entire premise it was sold on in the trailers does not exist. Because that part was supposed to take place in the last third of the game, which is nowhere to be found.
The game thus makes no sense as a narrative experience. That's not even touching the problems that the game has with the content that actually is there. The undeveloped characters, the repetitive side-ops, the stale, stagnant, and static "open world", the mission structure (with its insane credits spoiling the story) that forces you to finish the mission in a shit way by obscuring the objectives, so you would replay it later, the empty motherbase with 3 working doors, the timewasting motherbase building minigame designed to force you to buy resources with real money, etc.
The only real thing the game has going for it is its well tuned and polished gameplay, that they had three years to work on, because they obviously didn't work on anything else.
And it's been "sitting" for two weeks now. It just gets worser and worser in everyone's mind as time goes on.
177 pages of near unanimous dislike for it from those who finished it, and this is x2, with the first one being 300-400 pages long.http://www.neogaf.com/forum/showthread.php?t=1111262
The game, as a game, is a timewasting shitshow, that nobody who cares about narrative should ever play.
Metal Gear Solid games were always narrative experiences first, and gameplay experiences second, even when the narrative was batshit insane, which was a lot of the time. As a game that has no context, MGSV is quite okay. As an MGS game, it is TERRIBLE.