Recently I realized what was probably the root cause of this: computer science had emerged between 1960 and 1970. And it mostly came out of the engineering schools; some of it came from mathematics. And the engineering schools were mostly all men in that period. And the people IBM was hiring had to meet certain requirements: have certain degrees and have taken certain courses in computer science. And so they were almost all men because they were the ones that satisfied the requirements—because it was a discipline now.
