The Gorn are being established here as lacking empathy and having a very alien reproductive cycle and sense of values. All of that is completely consistent with their appearance in "Arena."
I'm going to try to re-watch Arena tonite. It might be consistent with their original appearance, but don't you think this characterization completely negates the anti-prejudice message of TOS’s Arena, of not judging people(or species) based on their physical appearances?
I'm not saying its inconsistent or some kind of plot-hole.