so they just disappear, block chain or not.
The actual video is not on the blockchain but in IPFS. And it get deleted if it won't get enough upvote to pay for the hosting.
It's not censorship it's capitalism which deleted your dTube videos.
For subscriptions on steemit you might want to try out https://steempeak.com/
I am planning to set up my own IPFS server and then seed my own d-tubes as I don't get many views anyway. My first attempt would hang part way thru the video but I will try using a Linux server next.
I also joined your German G+ alternativen community... but using a private window (not logged in) suggests the same problem of being shadow banned by Google.