Potentially, but I think just having a block list recommendation or trusted filter is not really censorship unless its being forced on someone without their desire to.
Discussion
A user can’t “block” anybody on nostr. You can only mute another user. I think you can make up any straw man scenario to become pre-outraged about.
¯\_(ツ)_/¯
It's just simply "i won't see your messages, shut my eyes of you, and will ignore anything from you" 😅
Even just quietly ignoring someone is its own form of censorship. By any means, you have made that person quiet.