Let's say you only have a cellular data plan, but it has a data cap, or your cell coverage is slow. So when a friend sends you a link to a video, you go to a library or coffee shop to download it to watch later. Is that "acting in bad faith?" I guess it gets in the way of Youtube's "right" to shove ads at your face, but avoiding the ads was not the point.
As was pointed out elsewhere in this thread, they failed to outlaw VCRs back in the day, so hopefully this nonsense will also get slapped down.