Not sure what the underlying sharing architecture should be. Use of distributed P2P systems tend to be a bit hostile in terms of user experience. Kind of the mentality of the associated crowd and often illegal content.
From a user perspective it should be just marking the Collection folder as shared and anyone with the link could view / sync it locally view it with the native viewer for that mime-type and optionally get updates .
It would be simpler and more efficient to have say front end WebDav servers cache the public content folder for serving / syncing. Like one author allowed to PUT but world readable . Also makes sense to have a flattened smol web version of the content for those who are on other systems.
Private / limited sharing would be a whole other world and I am not sure I want to go there yet.
My fantasy is more about public content publishing and making it easy, lightweight, inevitably beautiful leaving no space for advertising. Only content in the same way you can setup a
#geminiprotocol capsule but make publishing one click. The way Apple would have wanted it circa 2005 but not in a walled garden.
Ideally each person would his/her own domain and server but more realistically in the way we had Fediverse servers generous people could setup the public servers to make public content easily accessible in a subdomain / folder.
#RetroFutureComputing