I did say I don't really know how it works😅... But here's what I was thinking:

My limited understanding is that the blockchain works as a ledger. Basically, a list that can verify or confirm the authenticity and provenance of files. The way it's verified is by doing some very complicated math on some particular numbers with properties that allow for their authenticity to be verified but not forged. People have incentives to do this complicated math (that takes up power, time, money, etc.) because the blockchain rewards them with tokens or coins (which could be used to pay for special services on the platform, for example).

So, yes, the blockchain doesn't make files smaller, but it could work to verify their authenticity, and that they have not been tampered with. That way, anyone can host anyone's videos, but the ledger would guarantee that the video is the "original", as well as information about who first posted it, etc...

So instead of videos being hosted on 1 server, videos could be downloaded and made available by anyone to anyone at any time. The videos aren't smaller, but no 1 server would have more burden than any other, and it would be scalable since the users would host their favourite videos. Like torrenting?

Maybe it's not a useful tool in this case, IDK. It was just an ignorant suggestion really, as I said I'm not a dev and don't actually understand any of this... I just want a better YT.