YouTube wants to improve the well-being of content creators. To help this they are currently running a test where they hide the number of dislikes a video gets.
The dislike button will still be available in its usual place. But there will no longer be a public count of how many dislikes have occurred. This is being tested in response to feedback from creators.
YouTube has found that some users target creators to intentionally get their dislikes high. They are hoping that the removal of the dislike count will discourage this behaviour. Creators will still be able to see dislike counts from YouTube studio.
YouTube doesn’t want to fully remove the dislike feature, as when it’s used properly it can help creators understand viewer feedback.