Links to source articles below.
Yesterday 30 million users signed up for threads, which is already more than active users in the fediverse.
Furthermore, it seems that Meta hasn't launched threads in the EU due to uncertainty regarding the Digital Markets Act. It is entirely possible that their intent to federate with other Activitypub instances is entirely a cheap way to avoid being labeled a gatekeeper and avoid other regulatory requirements or restrictions.
It's future use of ActivityPub to get better publicity or scrape a bit more data might be an added benefit but not it's true purpose.
We'll see if launch in the EU goes hand in hand with them turning on Federation. I suspect that ActivityPub and the Fediverse are merely an afterthought to them and a convenient way to avoid being impacted by certain regulations.
Edit: Found a brief overview of the DMA. Among other things they say:
"The DMA aims to ensure the interoperability of messaging services allowing users on services like WhatsApp to send messages to users on smaller services like Signal"
https://ec.europa.eu/commission/presscorner/detail/en/ip_22_6423
I would imagine being open to federation is all that's required for the EU.
Also, defederation doesn't mean they can't access federated data. They can even interact with it. It just doesn't get synced back to the original instances.
Unless Fediverse servers block Meta's servers IPs. That would be hilarious, considering how Meta and other shitty corpos blocks access from Tor and limits everything without login.
"Open internet? What open internet?"
We'll see.
Correct, which would dramatically reduce its value for marketing purposes, as federated instance owners get a constant stream of far more than can be viewed publicly.