Exactly! Which goes above my pay-grade and understanding … but I can imagine it’s a fundamentally theoretical question at it’s core … for any given decentralised protocol, what’s the set of answerable queries a user and/or instance can make? Or something like that (like I said, above my understanding) … ie, what is and isn’t actually decentralise-able in terms of features and information that a user would find useful?
And intuitively, I’m guessing there’s a bunch of stuff that isn’t really decentralise-able. Even the way the fedi/AP works, AFAIU … is basically just viewing local data that is a duplication of originally external data (that has been subscribed to).
And so the more the fedi (or its users) start asking for utilities and features, with instance recommendations and “Join-x” web pages being perhaps a notable example, the more relatively centralised services make more sense. Though, thinking roughly of the DNS system, I’m wondering whether a more robust system that isn’t really centralised is the sort of thing the fedi needs for ancillary user-friendliness needs.