Where as Novak was brought up in the Slobdoan Milosevic (Former President of Serbia) brutal genocidal era. Look up Srebrenica massacre (when 8732+ civil Bosnians were massacred by the Serbs the biggest European massacre since WW2) and then NATO responded by Bombing Serbia in 1999.
(I'm no expert on Balkan history so I'm ready to be corrected if someone in Saddo lives in that part of the world. But that what's I've read but you never know who to believe)
Novak could easily been killed when he was a kid in the NATO response. He's talked about it many times. I guess that why he has a bit of that Ivan Drago "If he dies, he dies" vibe on the court
So basically Novak isn't from a HYPE COUNTRY. Not so much to do with his personality really. John McEnroe was a madman on court but he was from a hype country (America) so he was seen as edgy.
Nor does Novak come from a rich or well to do family (Rare in tennis). And all that bothers ppl. As if the audience says "You don’t belong here". But he does. Since he is a true fighter and one can actually learn a lot from his perseverance.