the new moderation is no moderation

applications may provide opt-in filters, such as:
- age of pubkey
- post frequency (spam?)
- number of reactions to posts (flat or algorithmic)
- kinds of reactions to posts
- llm analyzed quality of posts
- amount of pow applied
- semantics used in post
- exact words used in post
- mllm analyzed quality of media in posts

filters may be applied with different strategies:
- post basis
- hide all posts if n posts by npub match filter