What keeps getting lost in this discussion is the fact that young kids are uploading videos to Youtube. That should not be allowed, both de facto and de jure. It's up to both parents and technology providers to make this all but impossible.
"Users do not need to look for videos of children to end up watching them. The platform can lead them there through a progression of recommendations.<p>So a user who watches erotic videos might be recommended videos of women who become conspicuously younger, and then women who pose provocatively in children’s clothes. Eventually, some users might be presented with videos of girls as young as 5 or 6 wearing bathing suits, or getting dressed or doing a split."<p>Holy shit, just burn it down at this point. This is what happens when you just mindlessly optimize.