Adam Mosseri:
Second, threads posted by me and a few members of the Threads team will be available on other fediverse platforms like Mastodon starting this week. This test is a small but meaningful step towards making Threads interoperable with other apps using ActivityPub — we’re committed to doing this so that people can find community and engage with the content most relevant to them, no matter what app they use.
It will end up being de facto EEE, the same way it’s become functionally impossible to run your own email server. Sure you technically can, but the handful of big players block everything else and make it impossible to actually email anyone.
It’ll be like that on the fediverse. Big companies like this will dominate the space, refuse to federate with most others except the big players, and people will realize that unless you only want a mastodon instance with like 20 people on it, it won’t be worth the trouble.
That’s not even true, I run my own mailserver for private and a business and it works like expected.