It's now possible to watch YouTube videos from inside Google search results. Universal Search embeds videos into the SERPs if they match the search term well enough.
What happens if YouTube deletes the video? Do you think Google would adjust the SERPs or just leave the embedded video there?
This is a search result for Oban Star Races Sul and it contains two videos. (Which is a pretty impressive result for such a niche search, I think).
The big black square? That's what you get when you try and watch one of the videos. That black square persists for nearly 10 seconds (in tests so far) before the "this video has been removed" message appears over a still from the video.
In the old days of search - before Google - there was the constant annoyance of finding lots of dead / removed / deleted pages high up in the search results. It's a really bad user experience.
One of the reasons Google maintains the public cache link is to protect the user experience. If you find a web page in Google for a niche term that interests you and for whatever reason that page is gone or changed - you can look at the cache to see what was on the page when Google matched it to your search.
Right now Google's not able to protect my experience of the search in the same way with video. It is really frustrating when you find a video that matches your search, you click, wait, wait, wait some more and then get told "sorry, this video is gone".
Google can't simply cache these videos either - they've been deleted due to copyright concerns.
The solution is to quickly remove the video embeds from the SERPs.