Defederating means that for all intents and purposes beehaw and lemmy.world dont exist to each other its like if you and another person just agreed to not talk anymore and deleted each others phone number the posts that have federated over still exist but they wont be updated in any way

Defederating means that you as the user cannot interact or see comunities on those instances from this one and would need another account on a instance that is federated with them

Currently reading Hitch hikers guide to the galaxy really fun reads though it got weird in some places