Man of Steel had much the same problem. Its Superman didn't think for himself; he just followed the instructions of whatever authority figure was on hand, whether it was The Worst Pa Kent Ever, Ghost Jor-El (the actual hero of the movie), some random priest, or even Zod himself. When Zod told him "You have to kill me," Superman didn't think of a better way, he just obeyed an older man's instructions like he'd been doing all movie. He won the physical fight, but he did so by letting Zod win the philosophical fight, because he lacked the moral strength to stand up for his own philosophy and find a better way. Which is, again, reducing Superman to physical force and forgetting his where real strength lies.
Fair enough, but considering
Its not about "instantly" killing their enemies, but a decision based on the act being the only choice. In Man of Steel,[/I] there was no way to talk Zod out of his attempt to incinerate a family in the second he was trying to. This was no Donner film, where the goofy villain could be plucked by the collar and deposited in jail like laundry delivery. Quite the opposite: Zod--a more experienced and arguably more powerful Kryptonian was not not going to be reasoned with (made clear by the plan he set in motion), which was a great mirror of real life, as anyone who had the misfortune of dealing with violent or murderous individuals knows there's going to be some who--under no cicumstances--going to listen to assumed "reason" or be talked down from committing violent acts. This is the why anyone who actually watched MoS (without their self-imposed cartoon expectations of superhero characters) understood Superman's last-second decision; he did not kill Zod because that's his habit or desire. He killed when there were no alternatives in-universe. It was a powerful, effective scene, that did not water down consequences in order to fit Superman into a selective cartoon box which would not fit with the nature of the story, with its serious subject matter.
The same applies to MCU Captain America (Rogers); despite some seeing him as the most "golly gee"/"milk drinking type of characters, he--like Superman--knew when killing was necessary. In The First Avenger, there was no negotiating, trapping or stopping the Red Skull. None. Millions were minutes away from death, and Rogers was dealing with a man Hell-bent on mass destruction. Rogers boarded the Valkyrie to kill the Red Skull, not negotiate with him, or go in with some psychobabble attempting to talk him down. The audience understood that beacuse they were mature enough not to expect cartoon solutions to grave problems. In The Winter Soldier, when it was time to stop the Hydra-controlled carriers, Rogers did not hesitate in killing any who got in his way, with one exception--Bucky--because he knew his friend had survived, but there's no doubt he would have killed the Winter Soldier if the man behind the mask was some unnamed assassin.
Superman in Man Of Steel was still learning, and part of learning is fucking up.
Yes, the 'years of experience' Superman from the comics might have thought of a way to end that situation without killing Zod. This one does not have that experience yet. And he hated what he did 0.5 seconds after he did it.
Which is literally the whole friggin point of this movie. Yes, Pa Kent was completely wrong in this movie. That's the point!! Clark needed to learn to move on and form his own point of view.
Now, I know some people on this forum grew up with a 'established Superman'. And I also know these people will now write essays on how wrong I am for having a opinion that does not suite them. But we all learn from mistakes. To think that Superman was infallible from the start is a near childlike approach to worshiping a deity.
Becoming the person Superman is, requires years of learning how to the right thing. I am now 42. I still fuck up things and learn from it. This 'Superman was born perfect' image is just silly.