In this specific case, I think it's more that they had numbers on use vs. abuse and decided it was too expensive to maintain.
There was no way to have those numbers until the feature existed, so of course it got built. But once it got deployed, oh well... The public didn't use it in a way that makes sense to maintain.
Some creators I follow have said they wanted to use community translations but didn't because the feature was underdeveloped. Particularly the fact that contributions are anonymous so there's no way to build trust in a particular translator, every translation for every video needs to be scrutinized and they just don't have time.
But from Googles beep boop robot analytics perspective they just see that nobody is using the feature and assume it's because nobody wants it.
It's almost like Google's product owners have no idea how to build and maintain comprehensive products. If people aren't using a feature, figure out why and can it if it's not being used because of a lack of interest instead of said feature being poorly implemented or maintained.
Does Google talk to anyone outside of their engineering bro culture?
Google Developers video [0] describing exactly how you should speak to users to get feedback: usability tests. This is pretty standard in the UX community. Here's Steve Krug, author of the Amazon top-selling book on web design "Don't Make Me Think," showing how to do it similarly [1].
There was no way to have those numbers until the feature existed, so of course it got built. But once it got deployed, oh well... The public didn't use it in a way that makes sense to maintain.