Has anybody considered the idea that boosts from non-Meta properties to Threads could legally be used to build ad profiles? We already know they do that sort of account association with non-fedi accounts.
EDIT: Looks like that's absolutely the plan. From the privacy policy
"Information From Third Party Services and Users: We collect information about the Third Party Services and Third Party Users who interact with Threads. If you interact with Threads through a Third Party Service (such as by following Threads users, interacting with Threads content, or by allowing Threads users to follow you or interact with your content), we collect information about your third-party account and profile (such as your username, profile picture, IP address, and the name of the Third Party Service on which you are registered), your content (such as when you allow Threads users to follow, like, reshare, or have mentions in your posts), and your interactions (such as when you follow, like, reshare, or have mentions in Threads posts).
We use the information we collect for Threads for the purposes described in the Meta Privacy Policy, including to provide, personalize, and improve Threads and other Meta Products (including seamless personalization of your experience across Threads and Instagram), to provide measurement, analytics and other business services (including ads), to promote safety, integrity and security, to communicate with you, and to research and innovate for social good."
https://help.instagram.com/515230437301944?helpref=faq_content
I don't fully understand—would Meta be able to serve you targeted ads based on your non-Threads fediverse activities? Where would these ads appear? How do they know it's you just from your fediverse accounts?
No they would associate your boosts and likes from your fedi accounts to existing known (some Facebook or Instagram based) ad profiles. Here's an article about that as a practice: here. That info would then be used in pretty much every location that you already see targeted ads, folding you into the existing Meta ad machine without you ever agreeing to a TOS or making an account.
From what I understand, those shadow profiles are based on information that Meta gets about you from other users, or through things like cookies and tracking pixels.
Suppose that Meta builds a shadow profile for each fedi user, then how would they link it back to you? They cannot get your IP address from just being federated with your home server, and they cannot inject a tracking pixel to your server's website. Is there another way that they could use your fedi activity to serve you targeted ads?