Earlier quoted context omitted.
> In that case we'd expect a human with perfect drawing skills and perfect knowledge about bikes and birds to output such a simple drawing correctly 100% of the time. Look upon these works, ye mighty, and despair: https://www.gianlucagimini.it/portfolio-item/velocipedia/
You claim those are drawn by people with "perfect knowledge about bikes" and "perfect drawing skills"?
Most humans do not have perfect drawing skills and perfect knowledge about bikes and birds, they do not output such a simple drawing correctly 100% of the time.
"Average human" is a much lower bar than most people want to believe, mainly because most of us are average on most skills, and also overestimate our own competence — the modal human has just a handful of things they're good at, and one of those is the language they use, another is their day job.
Most of us can't draw, and demonstrably can't remember (or figure out from first principles) how a bike works. But this also applies to "smart" subsets of the population: physicists have https://xkcd.com/793/, and there's this famous rocket scientist who weighed in on rescuing kids from a flooded cave, they come up with some nonsense about a submarine.