He probably didn't know how to throw a punch correctly in the beginning and didn't hit hard, once he learnt though....
Skill wise, GGG > KK. Achievement in the professional ring at this time, KK > GGG, but that could change. Also, Kovalev has higher chances to lose at his weight than Golovkin.
True, it wasn't much of an argument, but one hell of a prediction statement. RocNation has already showed how Little g blatantly ducked Ward and how K2 used all kinds of weak excuses to justify his ducking. :yep