Earlier quoted context omitted.
To be clear, they aren't removing the button, or a way for users to register their dislike or track that they already disliked a video (I assume), just the count of how many other people disliked it. As a matter of engagement, I'm not sure how much that statistic brings to the table. I agree it might make filtering out crap content somewhat harder, but I'm not sure how good it ever was for that. It might be that the…
Personally, I have frequently wished that the downvote button on youtube _comments_ wasn’t fake. (Last I heard, it currently doesn’t even send a packet to any servers when you click it. It used to, until google+ iirc [edit: see correction/update provided by voussoir in the reply. Turns out it does now. Thanks for the update/correction.]) The inability to downvote substantially alters what is said/ranked highly, I thi…
Just tested. It makes a post to
/youtubei/v1/comment/perform_comment_action
with a parameter ?key and a payload containing "actions" both of which are long alphanumeric strings.