If a comedian makes a joke that is offensive, there will be natural consequences. That is, less viewers, less audience members, etc.
Statistics show that the majority of content and posts on social media are actually done by a small group of people. In which case, it is not for a vocal minority on social media to decide. It is up to the actual majority of the population by which that entertainment is supposed to cater to. I definitely don't think there should be any legal consequences outside of what would already be considered breaking the law (i.e. call to violence, etc).