How is this an example of failed privacy?
YouTube is a video sharing site. People pushed a button to share their videos. They wanted people to see these.
These videos aren't much different than what you find on Facebook or Instagram today, it's just that over the past decade people have gotten better at naming and categorizing what they post.
The real quirk here is that the app made it way too easy to upload the default filenames, so we can now search for them specifically like a little time capsule.
