Embrace, extend, and extinguish (EEE) - We don’t think they can. If anyone can explain how they technically would, please let us know. Even if Meta forks Lemmy and gets rid of the original software, Lemmy will survive.
It doesn't start out with maliciousness. The rank and file technical staff at Facebook aren't evil. Facebook understands the value of top tier tech talent and top dollar buys you smart people.
The initial federation is rough, but the problems are resolved surprisingly quick. None of the doom and gloom comes to pass, and Facebook consistently acts as a trustworthy actor. Their employees aren't really different than their open source counterparts. They make good faith contributions to open source codebases. Their collective experience with distributed systems proves useful in solving growing pains as the Federation grows.
They eventually start to make proposals to ActivityPub. There's outrage but no one can come up with good technical objections, so they are approved. The doom and gloom didn't come to pass, and looks like it never will.
Facebook doesn't need malicious intent for what's going down. It slowly, maybe quickly, becomes the dominate actor in the space. Facebook is pouring money into making Threads the best it can be, and what's wrong with them trying to build an audience?
Thread's improvements set an increasingly high standard for what people expect. More uptime, cleaner UI, more responsive API calls, more personalized frontpage algorithms, higher resolution videos - more and more features. More and more cost. Even people who kneejerk reject Facebook recognize how much better their site is. There are still important reasons to go with Lemmy or Kbin over Threads, but FOSS projects have never been good at making their case in ways random-not-technical people can understand, let alone why they should care about them.
After a while, Facebook starts walling people into their platform. Starts with little things like how Reddit added video and picture hosting to replace Imgur et al. It's not malicious, but rather from TPMs who are under pressure to increase engagement. After a while what else is there? Just don't turn the heat up too many degrees at once.
It's wrong to think of Facebook as a uniquely bad actor. This isn't 90s/2000s Microsoft with blatantly transparent EEE aims. There have always been bad actors. There will always be bad actors. There are bad actors with us right now.
Facebook needs to make money, and they won't do so by directly charging users. There's only one path forward for Facebook in this, and it will come at the expense of its users and everyone else in the Fediverse.
Build something useful, then put up walls around it, and then exploit it for profit; the internet's monomyth. You don't have to read the writing on the wall, but it is there. Federating with Threads is signing your own death warrant.
If the Fediverse experiment is going to survive, it needs to be able to withstand these bad actors. One of the ways it can do so is to recognize and reject them. Facebook has so many resources and so much power and we don't have to run the experiment to know where this will go. It is important to explicitly say "your goals do not align with what we are trying to build, and therefore we will not voluntarily interact with you."