[amadeuspagel]

I'd be surprised to learn that it's blacklisted from any feed readers. That illustrates the usefulness of separating reader app and hosting.

[irusensei]

Pretty sure it happened to Gab nodes. In this case justified (and probably with a bit of push from Apple and Google) but the precedent exists.

Slightly related Google blocked Element a few years ago because something posted on a federated instance. I think they strong handed matrix.org to implement moderation on the default servers.