The pyramids analogy may lead to a different line of reasoning: not only they look useless (making all the effort and complexity put into those unnecessary), but at least Aristotle claimed (not sure how accurately though) that they are made to keep people in poverty and occupied, in order to preserve a tyranny. Akin to the modern concept of "bullshit jobs".

The list of accidental complexity sources looks rather short. Off the top of my head, I can think of CV-driven development, of developers not being aware of basic tools, reaching for heavy and marketed ones instead, of awkward regulations pushing to silly solutions, of simple incompetence, of the NIH syndrome (or does that qualify as "creative temptation"?). The "Legacy systems and technical debt" point is applicable to newly developed systems with poor planning and strict deadlines as well. And then there are all the arguments about what is simple and elegant (or not) in the first place.