But if you go to https://kbin.social/d/threads.net (obviously doesn't work yet), then you can block the whole instance, yourself, for your own account. It has the same effect as the server defederating, but it only affects you.
The only reason why that solution wouldn't be acceptable is if you believe so strongly against the very concept of Threads that you want to make that choice for everyone else. You want to forcibly hit that button on everyone's account and push your beliefs and opinions onto others.
If you simply don't like Meta, that's fine - I get it. I want to use FOSS stuff to see my friends. I want my friends to appear in my feed, and I want their hashtags to be sorted into my magazines. My wish to see my friends is just as valid as your wish to not see anyone from Threads. While Threads has some questionable people, they aren't the majority. It's much better for me to block the individual accounts that cause problems than it is for me to lose the ability to talk to all my friends.
Kbin gives you the power to go to the domain and block it yourself; this isn't Lemmy. Why do you want to take that choice away from everyone who is okay with people from Threads in their feed?
I'm aware of the history - I used XMPP myself, for a long long time. I'm mad it's effectively gone.
Heck, on my Windows Phone once upon a time I could have chats with SMS, Facebook Messenger, and Google Hangouts all without leaving the stock native texting app. One by one they all broke and faded away.
But my point is - is the fedipact a better outcome?
My thought is no, it isn't. The intention of the fedipact is to split the fediverse in two - the side that federates with corporations, and the side that doesn't.
But the issue is that in splitting the fediverse when it's still so young and fragile, you're going to inherently kill it. Even if people maintain accounts on both sides of the divide, time is finite. People will make a choice to participate in one side of the fediverse or the other, knowingly or not.
My gut tells me people are going to want to go where the network effect is strongest. They're going to go where they know the people, where Wil Wheaton or Arnold Schwarzenegger might randomly pop up in the replies to a post.
And this is going to cause people to choose the side of the fediverse that gives them that interaction. Some may still choose to stay true to the fedipact - just as people do still use XMPP and IRC - but if the fedipact goes as intended, the fediverse will splinter and most people will go to the side with their friends.
I don't see how that world where the fedipact is successful is any different than the option 2 you laid out. The fedipact has caused 2 fediverses: one that has lost the network effect and is beginning to decay; the other dominated by a corporation. The fedipact side will have few people left because everyone left to talk to their friends on Meta.
The only way forward is to hope for option 1. Is it foolish? Maybe. Meta is a corporation that wants money. XMPP died a bad death. You can even argue that email is dead as an open protocol now - ever try sending an email message on your own server?
But we can hope for a situation like what we're seeing with ZigBee/Matter where an open, clear standard is maintained. And maybe that'll change in a decade, but the only thing the fedipact does is remove any hope for that at all.