People could never take jokes. It's funny, then when it's about you, it's not so funny. The problem isn't that people don't have thick skins. It's that social media is a megaphone for stupidity. My friend tells black jokes. Sure, they are inappropriate sometimes, but he isn't yelling them from the bar counter. A private joke between a handful of people might make you a racist/sexist/bigot, whatever, or it might not. But when you are a public figure (even a lesser known one like North), and you post on an absurdly public medium like Twitter, everyone who can take offense will take offense. I think there are probably less than a dozen trans people in my town. I wouldn't walk up to them and make fun of them because it's rude. The same way that I don't like people making old white guy jokes or comments, though it seems to be the only "safe" bastion left. You are free to feel however you want feel. You are also free to say whatever you want. But your employer is also free to fire you for harassment as well. Go back to 1930 and tell those southern lynchers that black people are equal to white people and see how thick of skin they had.