James Bridle has a terrifying and important article, it’s pretty long but the most important point is that people and businesses are systematically generating new videos for YouTube that appear to be tame pirated copies of shows like Peppa Pig but after a few minutes they change to be really awful and the YouTube app and site for kids don’t filter these out:
A step beyond the simply pirated Peppa Pig videos mentioned previously are the knock-offs. These too seem to teem with violence. In the official Peppa Pig videos, Peppa does indeed go to the dentist, and the episode in which she does so seems to be popular?—?although, confusingly, what appears to be the real episode is only available on an unofficial channel. In the official timeline, Peppa is appropriately reassured by a kindly dentist. In the version above, she is basically tortured, before turning into a series of Iron Man robots and performing the Learn Colours dance. A search for “peppa pig dentist” returns the above video on the front page, and it only gets worse from here
The reason why this crap skates by is because YouTube (and Google, and other companies) refuse to take responsibility for moderating what they host. Instead of hiring more people to moderate these things, the moderation is offloaded to algorithms and viewers.
Even if you only start a video on an official channel, auto play and the recommendations next to and after the video may take a viewer to another one.
tl;dr: Don’t let your kids watch YouTube. If you don’t have kids, please let your friends who do know about this problem.