YouTube Channel Hub is a private tool that a YouTube creator runs on their own home server for their own channels. It announces new videos on the creator's Discord server and shows the channels' analytics on a dashboard that is only reachable from the creator's home network.
It is used only by its owner. It is not offered to anyone else, and nobody else can sign in to it.
With the owner's permission, it reads the owner's YouTube analytics through Google's read-only access. It cannot upload, change or delete anything on YouTube.