Very informative, thanks for sharing.
The author is definitely qualified to speak on XMPP and ActivityPub but one thing I noticed is all protocols and technologies mentioned really had no other alternatives for communication. Users flocked because there was nowhere else to go.
Imagine Lemmy.world was owned by Meta and today decided to federate only with those who paid it.
It is in the power of users to host their content on instances that will not turn on them - which unfortunately means not holding discourse on monitized instances
I too am worried about what happens when instances start beefin and defederating.
But if a corp such as Meta owned Lemmy.world and one day decided to charge others for the right to federate, then it is also shitty.
The predatory practice of Big corps is offer service at a loss and once enough people on board, force users to pay to keep using.
Current Lemmy(ers?) have to realize this and not post or interact with monetized instances to avoid putting their content behind a paywall.