[red_admiral]

The interpretation in the book "Programmed Inequality", albeit specific to the UK, is that in the early days programming and adjacent tasks involved a lot of manual labor (punching cards, moving tapes around), for which companies employed women to do it as cheaply as possible.

When tech jobs switched to requiring fewer humans, but ones with much more responsibilities and the ability to make operational/strategic decisions and to contribute to the design of the systems as part of implementing them, then companies moved to hiring men.