Another way to think about it is through Graph Theory / Connectivity. https://en.wikipedia.org/wiki/Connectivity_(graph_theory)

In a federated network, what you see depends on your connections, similarly, what others see depends on their connections. Lemmy/Fediverse operators can defederate with nodes that are ‘bad actors’ (however their moderation team / operators define that), eventually the defederated node may not see much or be able to interact with much because of the limits of their connectivity.

Graph theory / connectivity is also how social networks figure out who you might be friends with, and how the NSA figures out who might be bad apples.

Math is cool =)