I don't think this could be "fixed" client-side. Mainly because that's the fediverse just doing what the fediverse does; it's not really broken. I don't really like it myself, but even if we had an app that pulls it all together and hides the duct tape, the fact still remains that if you interact on Beehaw communities, Beehaw users are never going to see you, your posts or your comments. You'll just be talking to yourself until such time as Behaw's admins choose to federate with us again.
From a user-experience standpoint, IMHO, the only way to clean it up on our end is to unsubscribe from all Beehaw communities so that they dont show up in your feed until Beehaw chooses to lift the shadowbans (which may never happen). Its a bummer, but they just dont want to be friends right now.
Alternatively, you can start an account on an instance everyone still federates with, but that could change too. Maybe choose a smaller instance that flies under the radar.
They added a check to their cluloudflare essentially cutting themselves off from the rest of the fediverse. They did this because their servers were struggling from the new users. They do eventually plan to reconnect with the rest of the fediverse. Also, they did this way before beehaw (and for completely different reasons)
Edit: I had old info, looks like kbin is properly federated with the rest of the fediverse now!