Right, like making them contractually promise to stop talking about it, in exchange for mutually agreed compensation. As i understand it, Freedom of speech is

Right, like making them contractually promise to stop talking about it, in exchange for mutually agreed compensation. As i understand it, Freedom of speech is not violated; you're still free to speak about it without going to government hunting you down. You're just breaking a contract you willingly signed, and have to deal with the ramifications of doing so.