IPFS Centralized?

I've been told that Dtube videos are on IPFS, on these other servers, but NOT directly on the decentralized Steem blockchain servers (witnesses). So, in other words, like another system, possibly a centralized server system stores the Dtube videos for a set amount of time but only for people who make enough money on the Dtube videos and only for about 2 years.

More Money Please

I've read that you have to pay more money to keep the videos on Dtube beyond 2 years or something. People need to correct me if I'm wrong but that's what I've heard & I can't see my older Dtube videos which makes me sad. That's why I stopped uploading to Dtube some months ago.