He is being extremely flippant with his descriptions, especially given the fact that a lot of modern day programmers are basically assembly line workers with barely any ability to troubleshoot the code they assemble.
Why is cooking a feminine activity, but most professional chefs are male?
Why was brewing beer a traditionally
female activity until about 150 years ago when the first large industrial breweries were opened by men, at which point it becomes (and remains) male dominated?
When there's significant money to be made, men drive women out as competition. Social mores shift to accommodate.
I'm not ever trying to make some feminist talking point here, it's just a process that you see repeat itself over and over since the industrial revolution started. It's not really all that surprising either, men are more prone to competitiveness and part of that is eliminating competitors where possible. Why not gatekeep? Every trade guild or union that ever existed has understood that principle.