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Really enjoyed that read. It's probably the only thing I've read that's helped me understand the differences between matrix and XMPP
My feeling is this is being written not just as a vent for ProcessOne adding a Matrix gateway to ejabberd but a warning to everyone thinking of setting up a trendy Matrix server or assuming enabling Matrix support will just be free. The eventual consistency model is expensive–for storage, for CPU/RAM, for client speed/sync–& everything it seems the Synapse & Dendrite servers are trying to do to speed it all up is in response of this likely fundamentally poor decision eventual consistency to ‘clone’ Slack/Telegram/Discord over allowing chat to be ephemeral & using forums for long-lived topics & Atom/RSS feeds for announcements.