Those are only using the ratio of likes and disliles of the users using those extensions.

So it can bias in a way that, say (this is an example, idk if this is true), the users of the extension are more “anti-windows” than the general population. So a video on the announcement of a new Windows release, would show as having more dislikes since the ratio of people who dislike Windows is higher.

(That’s how I understand the extension anyway, correct me if I’m wrong)