This should be in off topic because the mods will probably warn my post as usual.
This dilution of the word racism is why it doesn't mean anything anymore when you call someone a racist. It used to mean something and was properly chosen for people who actively held back minorities. I used to be a social liberal and then I looked around and realized that current social liberalism is insane. It's just a bunch of victims competing with each other on who can be more offended so that they can get the most amount of sympathy.
The guy made a racial joke that wasn't particularly funny. Should he be banned? I'm not sure. I don't know the rules regarding heckling. Is he a racist? Not enough information.
I don't think you would get warned for anything you said in this post. Regarding the "racial joke" here we probably don't have enough information.
Did the fan actually think the guy Patty is from Jamaica or is saying he looks Jamaican just because of his haircut? The fact that Patty is actually Australian adds a whole different layer to this because I think if the guy said "Australia called they need someone to wrangle their kangeroos" I doubt he would be banned for it.
In that vein if someone yelled out "Hey Tony Parker go drink some Bordeaux and eat a baguette cause you are waaashed up" would people think it was inappropriate?
That being said, the NBA wants it to be a comfortable viewing experience for fans, their families and the players and if people are finding comments offensive that are being yelled there isn't a lot the team can do besides kick the guy out.