The major elephant in the room here, which the memo doesn't seem to address, is that as late as the 1960's, computer programming was seen as a natural career for young women. Has biology changed that much in the last fifty years?
EDIT: it was more of a secretarial type of job. And women would socialize with other women on the job.
The point is that aside from the title, the IT industry then is in no way what we understand by IT industry now.