The article makes a good point but I wonder if it is an incomplete explanation. What would happen if Linus Torvalds walked away and there was no single leader to guide (or "dictate", depending on your point of view) its development? Would it begin to fragment and exhibit signs of Conway's Law?

I believe the answer is, yes, it would. While Linus is a stubborn and opinionated leader ("Benevolent Dictator For Life") it is those qualities, coupled with his extremely high standards, that have preserved the coherence of Linux's system architecture all this time.