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The Ministry for the Future makes open source social media look easy.
(en.m.wikipedia.org)
Book reader community.
The Three Body Problem also had a habit of coming up with really interesting concepts, which could have themselves been entire books, then dropping them after a chapter or two.
For example the device that could make anyone truly believe anything. They never got too techy about how it worked but after a chapter or two you really felt like you had explored some implications of such a technology on society.
I guess it's a bit much to ask a book about climate disaster to provide detailed insight into what the future may hold for Lemmy.