I used to think this myself--for many years. Then somebody on this board, probably when we were having this very same conversation 15 years ago--referred me to the screenplay of the movie. In the screenplay it states that Superman throws Zod to his death.
If true, that's better evidence than any other I've encountered for the "death" argument.
I've not read the script, but I do vaguely recall someone quoting that section at some point. What I remember is that it was clearly an earlier version of the screenplay, or that it was modified on set, because there were a number of elements that didn't line up with what's on screen.
And wouldn't the script (or a version of it) have also included the deleted scene of the Arctic Police hauling Zod and company away? So obviously there were different drafts of the screenplay, in at least one of which they explicitly survived. So the script as "proof" cuts both ways.
In any event, I would contend that the script is not the film, and like
Supervisor 194 and others, I feel that nothing about the scene as presented in the final film supports the idea that Superman killed Zod. That idea is completely at odds with the light, almost slapstick tone of the scene.
Yeah.
There isn't any other reason to shroud what happens to the three Kryptonian criminals in mist or for us to hear their fading scream as if they're falling to their dooms, without any further comment from the film, than that they're killed. This is after Superman crushes every bone in Zod's hand, and before he goes to beat the shit out of the trucker bully at the diner.
In films and television shows of this period, the audience is assumed to be supportive of the idea of villains getting their comeuppance and to be shedding no tears, if not laughing about it, if they're planted.
If the scene of the three being taken into custody, or some other similar scene, had made the final cut, then that would change things. But it was, in fact, not in the final film, nor was the matter followed up on in any sequel. So, the cues suggesting their deaths are all that remains.
This is well-argued, without the "Ha ha! Superman KILLS! Take that, wimps!" belligerent glee with which the subject is often discussed by the "Zod dies" advocates.
I will note, however, that I was part of the "audience of the period," having seen the film in the theater upon its original release, and it never even occurred to me to assume Zod and company had died. And to add to
Supervisor 194's anecdotal evidence, when I presented the question to my brother (also part of the "audience of the period"), his immediate response was, "What? Of course not! That's crazy!"
Obviously, this is one of those arguments that's never going to be resolved, though it will be revived and debated
ad nauseam. Hey, at least Snyder didn't leave any ambiguity about it in
Man of Steel, eh?