I think you're underestimating the human adversaries here. They've had ample (and in Krieger's case, decades) time to study Cybertronian technology and how to fight and subvert it. The whole point of Miles's MASK tech was to find ways to hide from and hurt Cybertronians. Additionally, this attack came out of nowhere during what should have been pomp and celebration. The Cybertronians were starting one foot behind to begin with. And since the big attack is a distraction from the smaller main group... I generally side with the idea that TF's have some serious advantages against humans (see the movie continuity for how to get that really wrong)... but they've covered their bases here.