The threat here is not about Meta harvesting already-public information. The risk here is about them doing to people off their network what they do extensively within their own network already: harvest information on your interactions with their content and users. Meta doesn't just build a profile of you based on your posts, its secret sauce is building a profile of you based on what you like, repost, comment-on, hover-over, etc.
Yes they can go out and spider ActivityPub content already, though they probably don't currently bother. But what they will gain by being part of the fediverse is the ability to associate your interest in their content back to your identity and learn out a graph about you. Boost/like/share something off Threads, and you've helped them build a model about you in a way that they can't currently do with all the free content out there already.
I'm not sure why other people aren't making this connection. Again, the threat is that Meta could extend its abilities to build a model on how users from outside its own user database interact with its content and users. They're known to already do this in the form of tracking pixels on 3rd party sites already, but this is a richer source of information.
That said, I also think the Fediverse is so tiny that this particular market isn't of much interest to Meta in reality. I suspect this feature will never launch.
Yes they can go out and spider ActivityPub content already, though they probably don't currently bother. But what they will gain by being part of the fediverse is the ability to associate your interest in their content back to your identity and learn out a graph about you. Boost/like/share something off Threads, and you've helped them build a model about you in a way that they can't currently do with all the free content out there already.
I'm not sure why other people aren't making this connection. Again, the threat is that Meta could extend its abilities to build a model on how users from outside its own user database interact with its content and users. They're known to already do this in the form of tracking pixels on 3rd party sites already, but this is a richer source of information.
That said, I also think the Fediverse is so tiny that this particular market isn't of much interest to Meta in reality. I suspect this feature will never launch.