But why is this surprising at all? Self-taught engineers most likely than not have the intrinsic motivation that CS graduates lack, who got into the field because of peer pressure or money.
And the raw talent too, that someone can master multiple disciplines is a sign of intellectual dexterity. Not too say CS graduates are not talented but self taught ones master more cognitive fields, which aid in their programming tasks because programming is a cognitively demanding job.
I was self taught from around age 12 with legit coding pre-ubiquitous internet and have a EE/CS degree. I was coding Mode X assembly demos in C, Pascal, and Assembly by 17. Most lower division courses were cake. I took 4 CS courses one time under a quarter system which is faster than a semester schedule. Many all-nighters, but got it done. The most important value of it is challenging your abilities and a common knowledge foundation. This is something self-taught only rarely or never receive. There are also too many people in STEM jobs to collect a paycheck while lacking passion.
And the raw talent too, that someone can master multiple disciplines is a sign of intellectual dexterity. Not too say CS graduates are not talented but self taught ones master more cognitive fields, which aid in their programming tasks because programming is a cognitively demanding job.