Since a few days all Blender videos on the OFFICIAL BLENDER CHANNEL have been blocked worldwide without explanation. We are working with YouTube to resolve the issue, but the support has been less than stellar. In the meantime you can find most of the videos on cloud.blender.org.
With our channel reaching > 100k subscribers, we have special priority support. So we contacted them to ask what was wrong. After a couple of mails back and forth, the reply was as follows (22 dec 2017):
Thanks for your continued support and patience.
I’ve received an update from our experts stating that you need to enable ads for your video. Once you enable, your video will be available in the USA.
If this isn't proof that we need something like PeerTube, nothing is. Actually I can understand that a commercial enterprise like Google don't want a hugely popular channel to not generate any income for them, but then don't pretend to be a free service.