Bluesky PDS' appear to be intended for invite only nodes for a handful of people at most. There are few compared to the overall scale of the social network.
There is an "app" which consumes data from these however this is exclusively run by Bluesky. Moderation seems to happen here.
A PDS does not have a standalone website and is practically useless unless accessed via the "app".
https://docs.bsky.app/docs/advanced-guides/moderation
According to Bluesky's own documentation, network wide takedowns are carried out by the firm.
"Relays are an optimization and are not strictly necessary. An AppView could communicate directly with PDSes (in fact, this is encouraged if needed). The Relay serves to reduce the number of connections that are needed in the network."