A similar thing happened a few months back to the channel Slope's Game Room. His was restored by YouTube themselves but it took him making a video and getting a lot of attention on it to get that change. If you or anyone you know has a contact at YouTube, now is the time to contact them.

I have a similar issue, on a far smaller scale though. Some spaces I moderate for have people understandably venting about *gestures wildly* and I want to engage, give hope where I can, but god is it exhausting...

Wish I had a solution, if you figure it out lemme know lol