The issue I see is ensuring that a distributed archive is comprehensive. How do you know what’s missing and needs to be added unless there’s a central coordinating process aware of what everyone already has?

The generational divide is just one instance of a broader phenomenon—similar divisions exist in adults between our constructed personas for family, work, friends, interest groups, etc.

Or maybe a server that lets you create multiple, “connected” accounts at the same time, together with a client that combines the accounts into one view.

I remember the steady turnover of social media networks leading up to Facebook—the joke was that kids would migrate to a new platform every time their parents joined their current one. I think there’s a kernel of truth there that’s still a potential weak point on Facebook: people want to have distinct, non-overlapping online personas for different social groups (family, work, friends, etc) without the overhead of maintaining multiple accounts. That seems like an avenue a potential fediverse Facebook alternative might exploit.