While I agree with that, this is the reason I doubt the claim in the article that "wheel" (including the axle connection) was only invented "once" — there is no support for it in the article.
As all of these technologies come into existence, some "inventions" become inevitable.
Sure, maybe a wheeled cart was constructed in one place first by 20 or 50 years, but we are talking about a time where knowledge did not travel far or fast. We had independent discoveries of the same thing in 19th century that were spread out by 20 years, I'd think it was even more 3500 BC.
