While I think most of us forum users are, I get the impression that the biggest proponents of activity pub and the fediverse as a whole aren’t even seeing privacy as even relevant. It’s a lot of talk of businesses having their very own instances to interface with the public rather than needing to rely everything on the whims of Facebook, twitter, LinkedIn, etc. Nothing with regards to the implications for surveillance, identity theft, spam, privacy or security.
Right now, we’re relatively under the radar because the fediverse hasn't really hit the mainstream yet. But I think it will, and once it does, everything we’ve ever posted will just get slurped up by data trawlers and the flood of spam will be inevitable. We’ll be juggling social media accounts just like we do with emails.
I don’t know if this is relevant, but I’d like to someday have my own kbin instance hosted on my own personal server exclusively for family. I imagine the instance being able to federate content from bigger instances, allowing members to follow people they like on microblogs or participate in federated forums from this privately maintained instance. But if anyone wanted a thread or magazine to be available to users from outside the instance, they would have to specifically opt-in to that option when creating it, and it would only apply to that one thread or magazine. Any other instance would just see our humble little family instance with only that one thing to federate. The rest of the instance would be an ecrypted enclave specifically for family accounts, and completely invisible to the fediverse.
Some sites are just desperate for traffic, it seems.