If you're worried about kids, better ban violent movies, video games, the news, and angry music. No, people have tried "think of the children" before but the children turned out fine.
As for other forms of media, we do prevent kids from accessing age-inappropriate stuff, more or less in line with developmental psych research [see: Huesmann, Moise-Titus, Podolski, & Eron (2003)]. YouTube is the odd man out here. The handwringing apologia over the appropriateness of a child entertainer using ethnic slurs would be laughable in any other medium.
Google has famously taken a stance on not being evil. It'd somewhat undermine this goal if it were unable to determine what evil is, and isn't.
They changed this policy when they got into the business of telling people what to think and control opinions.
Do we have a list of what Google considers to be a banned terrorist group for purposes of defunding?
Fine. Google should demonetize the videos or channels, but they shouldn't take down the channels altogether.
> searching something as innocuous as "feminist" gives the results it does
What's innocuous about feminist?
> it's not hard to see youtube as being one of the foremost contributors to extremism
That's what extremists say. That's why lgbt subs are demonetized.
> especially in kids.
I always get suspicious when pretty bring up "kids" or exploit "kids" to support an agenda.
> Real change won't happen until flagged videos get penalised in recommendations and search results too.
So you are advocating google censor?