The point of the contract is that if one is in breach the company can sue for damages and potentially remove the offending media.
The suing process would be through a legal body such as a court system, in this case federal court since the media is on the Internet, therefore the contract doesn’t hold any legal binding. No federal court would uphold a contract that violates the first amendment.
Contracts adhere to laws and rules just like any other legal document. You can’t just put whatever you want into a contract and have it be binding.