A hierarchy controls allowing or blocking YouTube categories, channels, and videos:
1) YouTube’s Restricted Mode overrides any other setting. If you have the Enable YouTube’s Restricted Mode option turned on, then every single video categorized as “restricted” by YouTube will be blocked, even if it is within an allowed category or placed in the Allowed Videos & Channels list. Practically all videos that YouTube categorizes as “restricted” are of no educational merit, so you should not encounter a scenario in which you want to allow a restricted video.
2) The Allowed Videos & Channels and Blocked Videos & Channels lists override Categories. A channel or video that appears in one of these lists will always be either allowed or blocked (depending on which list it is in), no matter if the Category it is in is allowed or blocked. Ex: If you have the Films & Animation category allowed, but have a YouTube video within that category in the Blocked Videos & Channels list, then the video will always be blocked. Similarly, if you have the Films & Animation category blocked, but then have an educational film within that category in the Allowed Videos & Channels list, then the video will always be allowed.
3) The Allowed Videos & Channels list always overrides the Blocked Videos & Channels list. You can have an entire channel in the Blocked Videos & Channels list, but if you have a single video from that channel in the Allowed Videos & Channels list, the video will still be allowed.
The following example illustrates how all three hierarchy settings work together:
Let us suppose you have the Films & Animation Category as allowed and have the Enable YouTube’s Restricted Mode option enabled. Instantly, all videos that are labeled as “restricted” by YouTube within that category are blocked, no matter what. Next, let us suppose that you have an entire Channel, “Shakespeare Films for Adults” (which falls into the Films & Animation category), in your Blocked Videos & Channels list because the majority of the videos in the channel are inappropriate… but, a teacher wants to show a single video of a film form that channel which contains age-appropriate content. You therefore place that single video into the Allowed Videos & Channels list. As a result, the entire “Shakespeare Films for Adults” channel is blocked, but the single video of the appropriate film from the channel is allowed.