BeOS was trying to disrupt the operating system market, so he was up against other programmers on their home turf. That example doesn't refute my thesis.

I hadn't heard of Shai Agassi before. He seems a better counter-example, although from his Wikipedia page it sounds like he went from getting a BSc in CS directly into 'entrepreneurship' and holding executive positions at various firms. I don't see anything in the way of an actual career writing software first, like Bezos had, not even a few years.

Jonathan Bulkeley doesn't have a Wikipedia page but from what I found he has a BA from Yale and never really tried to disrupt anything? Maybe I am missing something about his story.

Of course building a business is hard. I'm doing it at the moment so I'm well aware of that! I am not suggesting that merely knowing programming magically grants guaranteed success. But when you look at the type of people who are disrupting whole industries, at least in the sense the word is used, it invariably seems to be entrepreneurs who had some grasp of software or hardware engineering first.