Meta announced that users on Threads will be able to see fediverse replies on other posts besides their own. In addition, posts that originated through the Threads API, like those created via third-party apps and scheduling services, will now be syndicated to the fediverse.
It is a different level of scale, mastodon has about 1 million users spread over a bunch of instances. Threads has over 200 million users on one instance. also due to the network nature of social media the amount of connections and messages sent through those connections can scale exponentially with the amount of users.
Definitely can appreciate the carefulness here. Imagine they just open the floodgates and now some random Mastodon instance on a $5 VPS is getting hammered with millions of activities because they followed an account with millions of followers on Threads, and now it’s federating millions of likes and thousands of posts.
Meta is trying to be a good fediverse participant here. They could just come in and crush the entire fediverse and be like “lol should have gotten beefier servers”.
I’d hope it’s carefulness but it doesn’t seem like it. Facebook should want to destroy fediverse instances (from a business point of view), they are supposed to be a monopoly and the fediverse is their biggest competitor.
Only time will tell. They’ve definitely done their own share of EEE like for a while you could use Facebook Messenger over XMPP then closed it down.