I don't think being a New Yorker means you are destined to be as asshole. I'm from Jersey and generally don't care for people that meet the NY/NJ stereotypes. Maybe that's why guys like Rossman don't impress me.
There’s a line between being frank/brash and being an asshole - and often what side of the line someone falls on depends on how well you know/trust that the person has your best interests at heart.