Finding dead links to YouTube videos is increasingly becoming a frustration of mine. Whether it is because someone decided to private it or because YouTube decided to ban the creator for one reason or another. As an end user, it's frustrating to have no recourse to view them.
I don't know if there is a solution to this, but people who say that the internet is forever are demonstrably wrong.
I've noted that in my playlists not only are the videos deleted, but title of the video in your playlist is also deleted. So, say, if you had playlist full of music videos you like and want to remember, gone! Good luck finding out what you thought you were saving years ago.
A good solution to that is to google the link to the video and often times you may find a site that listed the title of the video before linking to it.
I don't know if there is a solution to this, but people who say that the internet is forever are demonstrably wrong.