i think the point they're making is that many learners in a given field (e.g., undergrads) don't typically critique the textbooks for those subjects. it's as if all the knowledge therein is complete and accurate, and research happens at some amorphous fringe beyond the textbook knowledge. it's intellectually "dead" to those learners, not that the subjects themselves are dead.
That may (how shall we know?) have been the point they intended to make, but the statement we have to work with is: "Any field of knowledge that has been dissected into a taxonomy must be dead."
Is there some nuance of uncertainty in there I'm not picking up on?
The word "dissected" is doing a lot of work there. "Any" makes it, arguably, hyperbolic. Obviously we can't take too literally any statement about a field being alive or dead. Research is alive in these fields but pedagogy is mostly not.
Well,we can put a man on the moon with less computing power than we carry in our pocket, and that's far from the most impressive thing we've accomplished in a long long list.
> hn is probably not where we solve epistemic dilemmas.
The repulsion to things like logic and epistemology on a programming website isn't the type of thing I believe we should strive for or celebrate, but I certainly can't disagree with your assessment.