Also, I'd argue more important than even having the hosters is having the content addresses. We need well-known immutable data for people to want in the first place. And traditional system bury data under so much mutation/indirection that it's hard to know what that content is, or that content-addressing even exists.

I highly recommend https://www.softwareheritage.org/2020/07/09/intrinsic-vs-ext..., which is about software heritage trying to get the word out to the larger library/archival/standardization community that content addressing and other "intrinsic" identifiers are possible and desirable.

Git and torrents I think is the best counterexample to the above, and there is probably more legally-kosher git and bittorrent usage, so I am especially bullish on Git hashing being the bridge to a more distributed/federated world.