A license to download some content that is otherwise publicly accessible? At any rate, copyright licenses cannot be enforced with smart contracts, because smart contracts cannot stop members of the public from making unauthorised copies. Copyright licenses can only be enforced by entities that have coercive power over individuals, e.g. courts of justice, but then the whole NFT becomes redundant because owning the NFT doesn't do anything, because in order to enforce your license you would need to have the proper paperwork and file a suit against the offending party.