Sarcasm can be used to be inclusive to someone (I’m saying this thing we both know to be untrue, imagine thinking otherwise!) or derisive (I’m saying this stupid thing you’d probably think is true because you’re an idiot and I want to make sure you know it.) I know friendly people who do the former a lot and nasty people who exclusively do the latter. I wonder if the former is more difficult to achieve among a foreign culture with a second language.