Torrent to me would be the ultimate, with perhaps a reward incentive to seed etc, but I’m not sure how that would be integrating into the current tech. I just don’t know much about it.
IPFS is currently here and used, so maybe that’s a first step? Not sure.. but I think both projects are very close, they just need some help.
RE: "Decentralized" YouTube Alternatives on Steem? Nope, Not Yet | A Detailed Look at 3Speak and Dtube