First of all, let me say that while the admins can do what they want, I think it’s pretty unfortunate that beehaw is defederating from .world and shitjustworks. I don’t want to see the fediverse fracture, I want it to encourage conversation with others.
But, beehaw has done what they’ve done. And I must say it’s annoying to be able to see their posts and comments and not engage with them. Plus, I could see their large, still visible communities taking away from ours without people realizing their own posts and comments aren’t working.
So will .world be defederating from beehaw? I don’t have a horse in the race, I’m jw
It’s not really a limitation of the software, it’s all up to each instance to decided how they handle things. Instance admins can code in a banner as you describe and they can make defederation transparent such as how Beehaw lists all linked and blocked instances. Every instance can do this, they just have to choose to implement it.