Was Jerry Seinfeld banned from any campuses? Or did he elect to stop performing at campuses? From everything I've read, it was a choice he personally made.
So, why did he make that choice? Well, because people didn't find his jokes funny. And moreover, they had reasons that they didn't find them funny. He couldn't stand the heat, and left the kitchen.
Free speech is not freedom from critical response. This isn't some failure of free speech on campus, it's a failure of one comedian to keep his material fresh.