It's an interesting experience that couldn't work in any other medium, but paradoxically enough, it doesn't work because it's a videogame. The moment I realized the things I was doing were morally wrong and still the game forced me to do them, I started feeling detached, and for good reason — I wasn't playing anymore but being played. I was being told a story instead of actively participating in it, preached about what the game wanted to convey. And I realize that's the whole point, that it is satirising war games and the possibility of choice would ruin the story, but at the same time, not being able to choose ruined the game side of it.
It's not about linearity, either. Videogames are all about goals. A game with a heavy focus on narrative and no choices like God of War works because the goal of both the player and the developer is the same: to aid Kratos and get to the end of the story. Same thing for Gone Home or Edith Finch, in which the players wants to merely be told a story.
In Spec OPS, their goals eventually start to drift apart: the developer wants to keep telling the story, while the player wants it to stop. And that's when it lost me. The degree of interactivity videogames allow when compared to movies and books, in which we are merely consumers that don't take an active part in any moment, makes it hard for me to simply accept moral quandaries whose outcomes are imposed on me. It's one of the reasons I didn't quite enjoy the direction The Last of Us 2 took. It's a great story about violence and revenge, but it loses its meaning when it forces us to do bad things and then try to make us feel bad for it. I didn't choose to kill all those people: the game made me do it. Instead of being moved by it, I feel cheated.
Maybe I'm being old-fashioned and I'm just not used to games trying to attain an emotional response this way, but there's gotta be a better way to tell those same stories without detaching the player's will from it.