Here’s a pretty thorough explanation of why this Meta app is dangerous for the Fediverse.
https://fediversereport.com/meta-plans-on-joining-the-fediverse-the-responses/
I’m still trying to wrap my head around Fediverse concepts as well but the thing that stands out for me is that there is a history of private companies effectively killing open source projects.
For us, the vulnerability is ActivityPub. If Meta begins “contributing” to a foundational Fediverse technology, they have the resources to extend the protocol in a way that benefits Meta only, at a pace that only a company with the resources of Meta can.
Should be able to if the different instance federates with this one