There are probably some cases where the answer is yes, because a math major who is now a software engineer has had to put in the extra effort to learn the compu

There are probably some cases where the answer is yes, because a math major who is now a software engineer has had to put in the extra effort to learn the computer science, and the computer science major never needed to do quite as much practice working with abstractions. Most people who go into software without a CS degree learn the practical side of things quite well out of necessity. I expect math majors are more likely than most to pick up the theoretical side even when self-taught, since the level of math involved is what makes it difficult for most people. But regardless of the greater level of self-teaching, the math major is unlikely to have had as good a survey of CS ideas as the CS major. Edit: I agree with everyone else who says that major in school isn't a very good predictor of software engineering ability. This is just my opinion on the direction of the small part that does come from major is.