Adafruit does run its own forum but this is about live-streamed video that is also stored for on-demand viewing. And as the post mentions, the video in questio

Adafruit does run its own forum but this is about live-streamed video that is also stored for on-demand viewing. And as the post mentions, the video in question is not gone, they do the stream on multiple platforms simultaneously, for instance it's still on YouTube. They do this not only because of the expense of operating your own video hosting infrastructure but also to be where their audience is, which is in multiple places.