At the end of the day, it's the parent's/guardian's fault for knowingly letting their kids browse on a platform where anyone can upload anything.

You are putting way too much trust in an opaque corporation to provide adequate content for young children. Just because it's "Youtube" does not guarantee anything. In fact it makes it much more dubious of a site, knowing exactly how youtube functions and how google manages it (very badly—at least for children's content).

No one is forcing you to put your kids in front of youtube. Please stop shifting blame when it's your fault for trusting random recommendations from an opaque, broken algorithm to filter endless random content, run by an uncaring corporation.