I might sound a bit elitist, but the sort of people who would join Threads would lead to step 0 of the enblandening of the entire fediverse. Not to mention increased bot spam. I say this as someone who is likely enblandening the fediverse.
I've personally no issues with corporate instances, in principle. E.g. if Ford wanted to create an instance to chatter about cars etc, I'm good with that. Even the likes of Google etc might be (very!) cautiously acceptable , despite their history of EEE tactics.
Meta, however, is like gangrene. There are 2 ways to deal with it, antibiotics, or immediate amputation. We do not have an antibiotic.
Meta will almost certainly poison community here on Lemmy. Whether it is accidental, or deliberate is irrelevant. It's the nature of that particular monstrosity. Lemmy doesn't have the mass, or history to absorb the damage they will cause. The only safe option is to amputate early and hope we can contain the infection.
The more I think about this, the more I think the beauty of decentralisation is really underlined here. With multiple instances some will defederate, while others will not. This way the fediverse as a whole can get the best of both worlds. The defederated instances are safe from any malicious deeds, while the others can still profit from the added content to build a bigger userbase.
Of course existing users are worried about what their instance does and many will be disappointed especially on the big instances. But even if the instance decides to take the route that the user did not wish, they can just move to an instance that shares their values.
Or it'll tear the fediverse in half, and when Meta's sudden but inevitable betrayal comes the other half will disappear into obscurity and eventual death.
Or we could wall the cancer off and hope the rest of the fediverse can continue to grow organically. That'd be my preference.
Basically Google did to XMPP what Meta will inevitably do to ActivityPub. That’s pretty much the only reason I agree with defederating from Threads.
Concerns about diluting the fediverse with normies are silly, since you can join communities that are interesting to you. And on the whole, a larger population on the fediverse is good for everyone.
This is my take. I honestly don't see how Google didn't just extend XMPP well past when it would have naturally died, and they only pulled the plug when it was clear nothing was going to come of it. I acknowledge that this is an unpopular opinion here, but I feel like that's just because this community is very biased when it comes to this kind of thing.
This entire debate is pointing out a glaring flaw that has been solved in Mastodon but has not yet been introduced to Lemmy, which is the ability as a user to personally filter / block all content from any instance through your account settings rather than having it done at the instance level. I think that were we able to do so at the user level, it would completely abate this entire concern for all but the most stalwart "fuck meta" people.