My boyfriend says nobody is being supportive of him

My boyfriend is a stand up comedian. Not a popular one. He's only gotten a few gigs. My brother is an actual stand up comedian and does it as a career. My brother has tried to give my boyfriend notes but he won't take them. The problem is my boyfriend is too offensive. My brother haggles but he wouldn't say the things my boyfriend has said. He's mocked several women's weight and made jokes about their weight being raped protection. My boyfriend's excuse is that when you go to these shows you have to have a thick skin and if you can't take the heat get out of the kitchen. Well his jokes just ruined his 22 year friendship. He's been best friends with his friend Mac since they were 5. Mac came to his show with me and my boyfriend haggled him but took the jokes way too far. He was talking about Mac's boyish body and that the security guards in juvi really liked him. Well Mac did go to Juvi in his teen years. And he was SA'd by a security guard. And my boyfriend was the first person he told. He joked about that for a good minute until Mac got up and left and my boyfriend said something like "He got out of there as fast as every MeToo victim when their "stories" get debunked,." Others started leaving. Mac blocked him on Facebook and my boyfriend can't believe he would do that and I told him he goes too far. Even my brother who is a comedian says he does. He felt like I was saying he wasn't a comedian and I mean.... He's had 10 gigs in the last 3 years.... Even his YouTube only gets maybe 100 views. But that's besides the point. I think if everyone isn't having a good time his jokes aren't funny. He said he's tired of everyone trying to bring him down and when he's successful living in a big house everyone is gonna wanna mooch off him. He told me to be supportive or get out and again says people know what they are getting into at these shows. I feel like there's a line but he doesn't wanna be with me if I can't support him