Atproto isn’t “many servers sending messages to each other”. It’s structured more like RSS:
1) there’s an app-agnostic hosting layer (and anyone can run a host, a bit like personal site with RSS)
2) then there’s apps, which aggregate over data from all hosts (a bit like Google Reader or Feedly)
So there’s no such thing as “defederating”. You don’t have many copies of Tangled beefing with each other. It’s more like you can run your own hosting for your own data (if you want), and anyone can build an app that aggregates from everyone’s data (Tangled is one such app).
1) there’s an app-agnostic hosting layer (and anyone can run a host, a bit like personal site with RSS)
2) then there’s apps, which aggregate over data from all hosts (a bit like Google Reader or Feedly)
So there’s no such thing as “defederating”. You don’t have many copies of Tangled beefing with each other. It’s more like you can run your own hosting for your own data (if you want), and anyone can build an app that aggregates from everyone’s data (Tangled is one such app).
If this got you curious, I have two longreads: https://overreacted.io/open-social/ (conceptual) and https://overreacted.io/a-social-filesystem/ (diving into the data model).