> the thread hasn't exploded into a XMPP v. Matrix holy war
Thanks for replying, that is definitely not my intention. My main concerns are interop, privacy and usability. I have technical/political criticism on both sides (XMPP/matrix) but as an end-user/sysadmin i don't see much difference in spirit/protocol between XMPP and matrix (except for decentralized rooms).
I'm currently using Jabber/XMPP for technical reasons. My two blocking issues with matrix are client side with element being really latency-sensitive (+ > 9MB loading), and server-side with synapse taking resources so the non-profits i know (eg. tildeverse.org/chatons.org/libreho.st) only provide Jabber/XMPP service. But like i said elsewhere in the thread i'll give dendrite a go.
My agenda is not hidden and is as simple as empowering users to federate across decentralized networks/protocols so we can stop arguing which solution is the best and stand up together against the corporate silos. This was stated in the goals of the joinjabber.org collective we founded a few weeks back: https://joinjabber.org/collective/about/goals/
I can assure you i have bitterness on both sides, with XSF mostly concerned with business use-cases (not free/non-profit ecosystem), and with matrix investing considerable resources into reinventing the same wheel as XMPP did two decades ago (a universal federated, bridgeable messenger). Despite everything, my agenda is as simple as "interoperability".
> as long as there's a way to map between them
I agree on paper. But in practice very few projects actually do that (only Hubzilla/Bridgy to my knowledge) which led to my question of potentially reusing an existing standard instead of coming up with an entirely new vocabulary. In my personal view, coming up with new vocabulary is also a valid approach if interop is not an afterthought.
> if folks have solved the problem elsewhere satisfactorily (...) to become the realtime communication layer of the open Web
I believe ActivityPub/ActivityStreams has solved many problems, and is already the most advanced/standardized federated social protocol on the open web (it's a W3C recommendation) despite not being especially real-time oriented. There is room for interpretation/improvement in the specs but "user profiles, posts, communities, sharing" (as in hummingbard) is definitely covered by major implementations in the fediverse even if "communities" use-case was not explicitly mentioned in the initial AP spec.
Still i made the effort to follow your link to Google Docs (seriously why Google? i made an exception for you but it's fucked up) and i better understand your concerns about reusing/mapping ActivityStreams to matrix vocabulary. So while i can't say i encourage you to reinvent yet another social federation vocabulary, having a strict mapping like you mentioned in the doc makes sense... but it should really be priority n°1 otherwise we're just splitting the ecosystem even more (see XKCD about standards).
Interoperability for social networks is really cool. People enjoy being able to comment on a Peertube video directly from their Mastodon client/account. I hope we can have matrix spaces (and hummingbard and others) part of this federated future as well. I don't believe standardizing a gateway/bridging mechanism is enough if interoperability is an afterthought (in the rest of the standards) because that's precisely the path that Jabber/XMPP took ~15y ago and it's failed dramatically.
Take care and keep in mind despite our respective opinions/criticisms, we all care for empowering and protecting users. Our enemies are corporations, governments and other kinds of oppressors, not other federated protocols.