If you are talking about videos that teach something, for most of youtubers out there that churn out quality content, they will have a library of videos that they will upload to an alternate site. Things will be back up in no time.

I wouldn't worry about it too much. What's the worst that could happen in YT is dead now, people go back to not wasting time on YT Binges.

When I think of situations like that, I think it's an ecosystem and if youtube would be limited or disappear lots of other services would spring up.