I’m in the camp of welcoming meta to the fediverse, BUT - not bending over backwards.
If they start making changes that affect federation for them, then that is their problem. Treat meta as a platform, no different to mastodon.
Remember that the fediverse consists of more than just Mastodon.
If meta makes a change and suddenly pixelfed can’t federate properly with meta anymore, it’ll be a shame, but it does not mean that pixelfed should make changes and add workarounds so that it is able to speak to meta again.
Meta might think they have the power to do this, but they only have that power if we behave like they do.
If instead we take an attitude of, it’s fine for you to be here, while you are being a good citizen, but if you start making demands - you are on your own.
AN (or even) multiple admins signing NDA’s does not mean anything for the functioning of the Fediverse though, admins are running software, many of them do not have the knowledge to go in and start making significant code changes to the protocol. That’s what Codeberg is for https://codeberg.org/fediverse/fep THAT is where changes to the protocol happen.