I am still quite new to Lemmy, but think I understood the basics. I noticed something strange though. I first created an account at a different instance, where I subscribed to a number of feeds. As that instance was temporarily overloaded one day I created a new account here, and subscribed to the same feeds. Now that the other instance is working normally again I decided to compare the two accounts in order to decide where to stay for good and I noticed that with the same settings, (Show all subscribed feeds ordered by Hot for example), it looks very different. The feed on the other account shows more current posts than the one here. If federation is working, shouldn‘t both accounts show me a more or less identical feed?
I find this a very interesting idea! This could also be done by large NGOs and orgs such as UNESCO, Doctors without borders, WWF etc., which would be more in the spirit of the Fediverse.