Funny, this move is exactly what YouTube did to their system of human-as-judge video scoring, which was a 1-5 scale before they made it thumbs up/thumbs down in 2010.
I hate thumbs up/down. 2 values is too little. I understand that 5 was maybe too much, but thumbs up/down systems need an explicit third "eh, it's okay" value for things I don't hate, don't want to save to my library, but I would like the system to know I have an opinion on.
I know that consuming something and not thumbing it up/down sort-of does that, but it's a vague enough signal (that could also mean "not close enough to keyboard / remote to thumbs up/down) that recommendation systems can't count it as an explicit choice.
> IIRC youtube did even get rid of downvotes for a while, as they were mostly used for brigading.
No, they got rid of them most likely because advertisers complained that when they dropped some flop they got negative press from media going "lmao 90% dislike rate on new trailer of <X>".
Stuff disliked to oblivion was either just straight out bad, wrong (in case of just bad tutorials/info) and brigading was very tiny percentage of it.
Youtube always kept downvotes and the 'dislike' button, the change (which still applies today) was that they stopped displaying the downvote count to users - the button never went away though.
Visit a youtube video today, you can still upvote and downvote with the exact same thumbs up or down, the site however only displays to you the count of upvotes. The channel owners/admins can still see the downvote count and the downvotes presumably still inform YouTube's algorithms.
I think that just the absence in official app and the existence of this tool makes this point largely irrelevant. Company in question could easily reverse this decision overnight as the data exist, but absent that people adjust to an available proxy estimate. It is interesting though, because it shows clear intent of "we don't want to show actual sentiment".
The official youtube stats (views, comments, upvotes) are not real/real-time either. But that's the best we have. And dislike numbers are in the same universe of credibility and closeness to reality. It's definitely good enough.
If you want downvote data be more precise, do your part and install the extension! :-)