So for the record, the author of the "pact" has been publishing blatant fiction under the guises of "unverified rumors" and nearly everything you said here falls into that. All of it has been confirmed false by either Meta or representatives of the fediverse who met with Meta.

Meta isn't making any special deals with large servers and basically no large servers have signed the pact. Most of the pact signatories are single user servers or similar, there's a handful of small to medium sized ones, and even those who are defederating Meta will not defederate the servers that do federate with Meta.

That doesn't seem to be true. There are a lot of instances that have signed the 'pact' to defederate Threads right away, but those tend to be mostly small instances.

Looking at the largest 30 or so instances by users most of them seem to have a 'wait and see' approach, which seems much more reasonable to me.

What's great is I can easily swap to an instance that is federating!

Unidirectional federation sounds like a nightmare on the UX side, so if that's the case I imagine it'd be Threads to Mastodon, enabling you to follow (but not interact) with Threads users.