There are sections that address this: 4. C) You agree not to access Content through any technology or means other than the video playback pages of the Service

There are sections that address this: 4. C) You agree not to access Content through any technology or means other than the video playback pages of the Service itself, the Embeddable Player, or other explicitly authorized means YouTube may designate. and 5. C)You agree not to circumvent, disable or otherwise interfere with security-related features of the Service or features that prevent or restrict use or copying of any Content or enforce limitations on use of the Service or the Content therein.