It might be sheer coincidence that saves the old man from losing the limb entirely to the hungry harpies, or something else. It doesn't really matter. Even here, wherever 'here' is, he knows his duty, and protecting civilians is part of it, and nothing of Palpatine's behavior or clothing suggests he's anything else.

The next to rake claws along the roof of the vehicle, desperate to get at the delicious helpless prey inside, falls in two pieces in a long bloody smear down the back window. Masamune's reach is considerable, and Sephiroth is much quieter than someone his size has any right to be - his sudden intercession whips the attacking birds' attention around from easy-seeming target to a much more obviously dangerous foe.

The vehicle .. IS good cover. Rain's not getting in, most of the wind is being kept out, birds can't effortlessly get in... it's just a little too far from the garage, diner OR convoy to make a run for it. There's something not quite right about Palpatine's rescuer, either the deadly equanimity or the way he braces against the passenger side and shoves, driving the entire vehicle sideways in a screech of metal rims against broken pavement like it's a fraction of its true weight; gradually the entire decaying vehicle is pushed closer to the convoy and a more durable place of safety foot by foot.

Any swooping avian intent on keeping its prize will die as efficiently as the first.