I think part of it just comes down to developers of each project having direct communication channels with each other, whether it’s poking each other over email, instant messaging, or direct messages; meanwhile kicking around topics in microblogging format (as something that can get buried to the timeline with everything else), sometimes makes it difficult. I do agree that SocialHub for whatever reason feels difficult to keep up with.
Essentially with FEPs, it feels almost like something that should be treated like trying to get a bill through Congress. “Hey, I’ve got this new proposal, I’ve talked to X and Y project, and they seem onboard, can I count on your support too? Is there any feedback you have on this idea?”
As for Mastodon: fuck it. Everyone else can continue advancing on together, and probably craft things in a “progressive enhancement” manner to augment new things, while Mastodon can act like the “Internet Explorer of the fedi” in it’s own little aimless corner. While the rest of us get to have: custom emote reactions, animation markup, search, post quoting, (now recently) post tipping, and whatever else comes next.
Or with locking down fedi: have some opt-in “strict mode” (that would otherwise ‘break’ federation, if it wasn’t opt-in) that could be advertised in nodeinfo, like in similar nature to HSTS with web browsers regarding strict HTTPS use; or if an actor has keys listed for Object Integrity Proofs, to trust that mechanism only for proving something authentic as originating from that user, and skipping whatever insanity of HTTP Signatures, same-origin, or other mechanisms, etc.