Okay. Here's what I'm saying. We've got Superman, and he has an "S" shield. It stands for the House of El in Kryptonian, but happens to look like an English "S" for "Superman."
Now, it would be weird if Zod's Kryptonian symbol looked exactly like a Z, and Faora's exactly like an F. That would be campy and cheesy, as I said above. But the genius of the symbol design here is that it is
vaguely similar to each respective English letter. See:
Note: the symbol is reminiscent of a backwards "Z" terminating in a long curve.
The symbol is reminiscent of an "F" terminating in a split curve.
Is it exact? No, but there are design elements there that make it
reminiscent, albeit alien.