Greatness? 27 7 6? That isn't greatness, he isn't even shooting 45% from the field. You call having a great season, greatness? There is a difference, he isn't a great player. He is a very good player, also averaging 4 turn overs a game, up over 1 per game from his career numbers. You are getting to caught in the moment, his team is average and he is shooting more than anyone, of course his numbers will look great.
Lebron is averaging just as good stats + better shooting percentage + has 10x better supporting cast to actually help him and still averages same+ better numbers than harden.