I’m aware of some stuff like that some instances have defederated from others for anti-communism (lemmy.world / hexbear.net), but that’s where my knowledge ends.
I’m looking to understand what instances to be aware of, each instances’ political leaning, defederation etc.
Not as much, personally. Piefed is even smaller than Lemmy from what I know. Most instances seem to be Piefed versions of existing Lemmy instances.