"And then after a few moments of having that experience, they would remember that they were in a video game and they would let go."

So basically what they are saying is that after a few moments of the experience of being forced into a level where the player basically had no choice in what their character could do, people's immersion was broken and they just accepted that it was a shooter that was ineffectively trying to present some sort of moral choice to the player?

It seems like people forget that Splinter Cell: Double Agent not only presented a similar experience three years ago, but did so in a way that allowed the player TO take choice and had gameplay implications for their action or inaction. All IW did here is make a level where you gun down civilians. The idea that even an agent under cover would participate in such actions is so implausable that it made it pretty impossible to take anything further in the game seriously. The fact that the plot after that moment gets more absurd by the level doesn't help either.