Is it possible to block all communities of an instance from showing up in the “all” feed? Or would you have to block each community individually?
On kbin yes, on lemmy I don’t think so.
Unfortunately you have block each community individually at this moment.
Functionally that’s the point of defederation, the only problem with it is if the problem instance is connected with one you are connected to it’s possible for communications to make a bridge that way.