“Threads is deepening its ties to the fediverse, also known as the open social web, which powers services like X alternative Mastodon, Pixelfed, PeerTube, Flipboard and other apps. On Wednesday, 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. The latter had previously been announced via an in-app message informing users that API posts would be shared to the fediverse starting on August 28.”
You are right, it’s easy to imagine the open source standard being a small financial threat. But a similar situation could potentially still happen, just without the malice the previous poster is imagining. Overall, large orgs make the biggest ripples in software development, so their choices of what to support affect what’s most available to users.