I hvnt watched it yet but "...the U.S. Tennis Association issued a statement saying that Friemel defaulted Djokovic “in accordance with the Grand Slam rulebook, following his actions of intentionally hitting a ball dangerously or recklessly within the court or hitting a ball with negligent disregard of the consequences."
So i agree with the ruling that he shd be defaulted.
As for Serena Williams, i remembered her as being penalized, but checking it she was docked a point and a game. I dont remember rn wat exactly happened but if the two of them had not been penalized according to the rules, more ppl wd hv said they excaped thru favoritism n being popular/famous. When throughout tennis history top players hv been penalized by the rules, i dont think Djokovic was dealt unfairly. Intent had no bearing, it was reckless endangerment that was the reason. He shd hv known better than to hit the ball away. N i still like Djokovic. Almost always have.