So this has been going around my head for a while now: What if they do not care about their users per se but want the few users they get to exploit the federation to shamelessly crawl the fediverse?
I mean... they get enough users that will subscribe to enough of the fediverse to make instances of every shape and size proactively deliver them our post and interaction data with free shipping, right?
So is defederating in the end not only a prevention against company controlled content that might flood the fediverse, but a measure to protect the users on the fediverse right now from ending up in Meta's databases just in the same way they would if they just had used facebook in the first place?
Defederation does not protect user data/privacy, not in the slightest. Anyone can spin up a Fediverse instance, play nice, and secretly sell or transmit the database to any third party. (I'm not even sure defederation blocks read access by the blocked server, regardless it's moot as a read access block on a single server is trivial to circumvent.
Forget it.
Defederation only has one effect: protecting write access on the defederating server. It does not prevent people writing about content from the defederating server on other servers (in the same way that you could comment about a Twitter post on Reddit by posting a screenshot), and it certainly will not stop read access.
I think people are misunderstanding what defederating gets us. Yes what you stated is all correct. You don't even need to have a server you can get the vast majority of the data you need from the public API and scraping the pages. It's more work but totally feasible.
What defederating gets us is that Thread would need to come up with a convoluted way of pulling in all the data and their users wouldn't be able to interact with other federverse accounts. You could see my Toots but not be able to comment or +1 them. You'd just see them as if you didn't even have an account.
So what is the benefit of that? Sounds to me like a shittier service than had they not tried to federate at all.