To build a folly is essentially to do something a second time, something at an inopportune moment. That something is always the memory of something forgotten, about which we can paradoxically say "There it is again."
Follies were misunderstood, purposeless constructions. They were often only small, extravagant gestures in a garden, easily whisking off the imagination to distant lands, a sort of time capsule built to awaken the memory and induce surprise in passers-by. They marked locations, organized secondary paths in a park, or simply predicted the arrival of better times—a demarcation, a sacred spot, a mysterious trail, a hill whose tragic rocky nature begged for a tower, a party, or the arrival of summer.
“It is demonstrably true that things cannot be other than as they are. For, everything having been made for a purpose, everything is necessarily for the best purpose.” — Professor Pangloss
There is a place for discussing technique, for which forums like r/Design, Designer News, and the like are well suited. Yet expecting these platforms to provide insightful, serious critical discussion is like going to McDonald’s for an artisanal sandwich. Sure, they may advertise that, but that’s not really what you’re getting.
To talk about the visual design of the Facebook feed, or the navigation, or the microcopy, to talk about any aspect of Facebook’s product design, is to talk about symptoms rather than deeper issues, motivations, processes, and incentives.
It would be like talking about Donald Trump’s website—a critical analysis Vinh suggests—instead of the nature of his political will or lack thereof.