I am a huge fan of Man of Steel in that it is a flawlessly executed movie. However, there are some thematic elements that I found problematic, and I wanted to go into those.
Put bluntly, the film is fundamentalist. It’s anti-science, anti-progress, and deeply suspicious.
Where in other incarnations of the Superman myth, Krypton fell due to the ills of its society despite its technological achievements, in Man of Steel these technological achievements are implied to be the reason for the societal ills.
Kryptonians developed the technology to reproduce without requiring a woman to endure carrying and birthing a child. Then they went beyond this level to the point of specifically designing each person.
Jor and Lara don’t like chance being taken out of the genetic equation, so they decide to have a child naturally, including 1) not manipulating genes in any way and 2) having Lara undergo pregnancy and labor. Why they didn’t just do 1 and spare Lara 2 isn’t addressed. The issue is treated as black and white: either you choose genetic manipulation/science, or you choose the natural way/tradition.
When you compare and contrast Kal and Zod in this context, the implication is that a large reason why Kal is “good” and Zod is “evil” is because Kal was born naturally. You even see this in Kal’s upbringing as Clark. He seems to be innately good; he doesn’t appear to have learned his goodness from the Kents. The question is never “Should I be good?” but “How should I express my goodness?” Meanwhile, Zod even comes out and says that he is acting as he was designed to act, that he can’t fight his own nature. Zod can’t be redeemed; he must be killed to be stopped.
This, of course, makes the more general, dangerous implication that some people are born “good” and others are born “bad” and that it’s impossible for a person to change.
Man of Steel does some unfortunate things: it treats complex issues as black and white; it rejects progress in favor of tradition; and it paints anyone who diverges from what’s “natural” as irredeemably “bad”. In this way, I’m sure the film is appealing to people who’d prefer a homogenous society. To someone like me who favors diversity, change, and the benefit of the doubt, though, it’s pretty troubling.