That also seems to be a risk with most centralized social networks these days as well.
Our LinkedIn profiles have been scanned by scrapers, Instagram photos used for facial recognition training, Twitter / FB posts replicated in a bunch of downstream places, archives, and search indexes. Not to mention data being sold to third parties.
At this point, I assume if I post it publicly online, it is no longer in my control where it ends up downstream and I assume it will be online somewhere forever.
Back in the old twitter days you could have screenshots of your tweets being displayed by a number of different 'dubious' accounts on instagram, completely out of your control.
That's just how it works and I accept the risk.
People concerned about that probably shouldn't publish on Bluesky. Private chat makes more sense for a lot of things.