Once more, world-building doesn't mean "intrusion of reams of information in the narrative" -- it means the necessary work to establish the setting that the narrative requires.
It would seem that professional authors disagree with your definition. "Necessary work" would seem to mean "writing." "Worldbuilding" is surrounding the writing with detail the reader never encounters. Even if it never gets onto the page, even if you end up discarding 90% of it...that useless detail is "worldbuilding" in the words of one professional writer of science fiction.
In D&D, there *is* an analogue (if there isn't, I wouldn't have expected this thread to go on for 8 pages

). The "necessary work" is entirely what the PC's encounter or are likely to.
Insofar as the thread is concerned for D&D, "worldbuilding" is composing reams of information that are largely irrelevant to what is happening to the PC's at the time. For instance, detailing Country X's government when the PC's are mired in Country Y.
It is, in fact, focusing on what is a minor detail to the point where it's a big deal. This is the "great clomping foot of nerdism," demanding a place for everything and everything in its place and placing this world up on a pedestal that claims it is worthy of this attention. It is the obsessive attention to detail that places knowledge of this detail as an end in and of itself, with little reason to care about that detail other than obsessive knowledge. Verisimilitude can certainly be maintained in absence of exhaustive detail, and, indeed, usually is.
What that misses is making the reader (or the players) *care* about it. It becomes a useless blob of intro text, irrelevant to their experience, important only to the creator as an excersize in creating.
Worldbuilding is unavoidable, it seems. You are always going to create more than you need. By writing triumphing over worldbuilding, the suggestion is that your world bends to the need of the story, or your players (the adventurers), that you avoid writing about the world when it doesn't matter to the group at hand and that whatever you write about the world *becomes* relevant to the group at hand. Worldbuilding is coming up with a government for Country X. Good writing is making that government relevant to the PC's mired in Country Y. Even if it means changing background details about Country X, Country Y, or the intervening Very Big Ocean in the meantime.
It seems to be suggesting the economy of creation. A writer should always be concerned with the story being told over the world it is told in. A DM should always be concerned with the adventures being had over the setting it occurs in. What's going to make this more fun, what's going to give me an interesting scene, a nifty encounter, a breathtaking combat, an epic BBEG?
I think D&D certainly has different requirements than writing, and the breaking point is going to be different, and that's part of what I was hoping to explore in the thread. I mean, neither the author nor I said "don't do worldbuilding." Just that your desire to make something compelling for your audience should always triumph over your desire to work out the fiddly bits of your pet setting.