Start with high speed (1gb/sec+) symmetric consumer network links and IPv6. Easily implemented, decentralized/self-hosted platforms already exist, but you can'

Start with high speed (1gb/sec+) symmetric consumer network links and IPv6. Easily implemented, decentralized/self-hosted platforms already exist, but you can't stream/share your vacation videos with your large family because your upload capacity sucks. Centralized services exist because individuals don't have the capacity to support a Mastodon or Diaspora instance on their own network connections. And more's the pity.