> we had companies that employed many people, so that the top level of the company could simply specify what they wanted, and the lower levels only had to focus on making individual parts.

I think this makes a perfect counter-example. Because this structure is an important reason for YC to exist and what the HN crowd often rallies against.

Such large companies - generally - don't make good products. Large companies rarely make good products in this way. Most, today, just buy companies that built something in the GP's cited vein: a creative process, with pivots, learnings, more pivots, failures or - when successful - most often successful in an entirely different form or area than originally envisioned. Even the large tech monopolies of today originated like that. Zuckerberg never envisioned VR worlds, photo-sharing apps, or chat apps, when he started the campus-fotobook-website. Bezos did not have some 5d-chess blueprint that included the largest internet-infrastructure-for-hire when he started selling books online.

If anything, this only strengthens the point you are arguing against: a business that operates by a "head" "specifying what they want" and having "something" figure out how to build the parts, is historically a very bad and inefficient way to build things.