Isn't it a blockchain?

They actually announced this around a year ago, but it was tentative back then.

Arweave is a file storage blockchain where everything is permanently embedded in the chain. If you put it there, it's staying there.

It also is fairly expensive to add something, especially large files like videos. I'm guessing Odysee will become a paid service for uploaders. Odysee is financially supported by Arweave right now, so they might be able to arrange free uploads, but I doubt it can stay that way indefinitely.