It’s worth noting that defederation-zero is not a practical requirement. There are some instances that just create loads of accounts and spam communities and reply to comments in communities that you are subscribed to. Of course for most instances they don’t support this and moderator prodding can solve this. But some instances are simply hostile and exist only to spam.

I do agree that I would like my instance to be defederation-minimal. Unless the other instance is being actively harmful or refusing to moderate at all (for example not retaliating for users who are breaking community rules) I would prefer to be able to see their messages and communities. For example I don’t personally agree with blocking Instagram Threads by default. Unless they show complete inability to moderate I would prefer to have the option to subscribe available. Especially because it allows an easy pathway for people to move from Threads to other fediverse instances (although maybe less relevant for Lemmy as it is more discussion oriented rather than personal profile oriented).

I would also like to be able to see per-user instance blocking. This would be a good tool for quick fixes to poorly maintained instances or instances who’s values I don’t agree with without affecting others. It could also serve as a useful signal to the mods. If dozens of people have blocked another instance maybe it is actually quite harmful and should be defederated.