MediaGoblin is working on a federated social photo and video sharing software. Kind of like YT, maybe?
One of the big problems with replacing YT, IMHO, is a good enough search system. The most important reason why people use YT is that you can find anything there. But as far as I've understood search is very hard on a federated system.
So, interesting thing: since iOS 13 iPhones can run SSH commands remotely via the Shortcuts that were added in that iOS version.
This opens a lot of doors to doing some cool things with iPhones. For instance, I use ArchiveBox to save and archive news articles and websites to my home server using this: basically when I find a page I want to archive I just hit the Share button, and you can set Shortcuts to appear on the share sheet. Then I just tap Archive (the label I gave the shortcut) and it sends it off to be archived on my home server, via SSH.
It's really quite a convenient solution.
git-annex is what I use quite a lot. It appears to have some sharing features which I have just discovered: http://git-annex.branchable.com/assistant/share_with_a_friend_walkthrough/
I am also pretty sure that git annex will work over tor, but this comes down to the exact functionality that you want.
You can download Freedombox for the Beagle Bone Black: https://freedombox.org/download/beagleboneblack/
So I quess the BeagleV could be an option.
However: Developers still need to port Freedombox over to BeagleV (which will take some time). Besides: From what I can tell BeagleV is a new system and has not yet been released. It has only been announced.