Doesn’t authenticated fetch kinda fix that? If users have the option to make their account private except to logged in other users, and if the server enables authenticated fetch to reject access from blocked / de-federated servers, then only logged in users from servers the server grants access to federate with will be able to view the content. That seems like some useful measure of privacy at least.
The only realistic thing that the NDA could have contained was stipulations around leaking details about Threads. Who cares. Some admins probably wanted an inside look so they agreed to not leak any details. That does nothing to put their instances under the control of Meta. Yeah sure the admins are “controlled by the contract”… to not share any secrets about Threads. Again who cares.
People dreaming up scenarios about the NDAs including clauses that let Meta control instances or their admins are delusional. As someone working in tech I sign NDAs all the time when I visit my friend’s companies. It doesn’t mean they have any control over me besides stopping me from leaking stuff that I see inside the company.