youtube-dl’s GitHub repo was taken down because the RIAA are a bunch of whiny spoiled brats. For some reason, some people are under the impression that just because GitHub complied right away to a absurd request, youtube-dl as a project is dead. At least for now until it finds a new home.
No it’s not, if you already have it installed it is still working. And if you don’t, you can install it just as easy as before.