MCU Villains: Why so controversial when criticised?

I know you were talking about all comic book movies as a whole. 
I agree, Zod was definitely the best of the Reeve Era villains. I loved how Stamp chose to play him as someone who takes himself WAY too seriously. 
Dirty Harry is definitely a good example. The only other ones that really spring to mind would probably be upper quality Shakespeare adaptations, and probably the original "Die Hard."