FWIW, I totally understand the view of "good servers block those servers" and it's obviously valid from a user and admin perspective. Defederation for your own safety is a strength of the Fediverse.
It's just that from a child safety perspective, victims are still harmed even if the problem instances are isolated—which is why we gauge the problem over the whole ecosystem and try to come up with solutions that will address it as broadly and thoroughly as possible.
@det I still find it troublesome how you try to conflate fiction with real child porn.
You went onto instances with a vast number of users and scanned around half a million posts to discover a few possible cases of real child porn.
Alright, so a few people are trying to abuse a service. It's still neither proportionate or respectful of free expression to engage in censorship.
It also wouldn't eliminate people trying to abuse a service, any service, or creating their own service, to engage in their abhorrent activities.
It should be noted that there are other instances which go further than that particular one (if I've guessed right) in tackling this, without the censorship.
These ones are also more communicative.
No instance, or it's users, would want this content on there. If you can offer your wisdom into bad actors, that is welcome.