Weren’t many of the programmers in the 50s and 60s women? The gender divide didn’t start to get really bad until late 80s, from what I understand.

A 'computer' was a predominantly female job role until.. I don't know, but some time post-war when we got bored of saying 'automatic computer' to describe the increasingly dominant method of computation.

Being a computer is different from being a software engineer or coder/programmer. Even when women were computers, they generally weren't the coders/programmers - this task was usually up to mathematicians or other subject matter experts who were generally men.

Women computers were replaced by software definable processors, not by software engineers.

I don’t think this is accurate.

The mathematicians/engineers were more like architects, and the women programmers weren’t merely compilers or input technicians. They actually wrote code, though this was also considered a drudge task back then (a view that was corrected later). Also, proximity to the hardware allowed many to grow out of their original job descriptions.

Until the invention of the phrase "software engineer", is my theory.

I'm still fairly new to the industry so I realize I'm likely missing historical context, but the only discrimination I've seen has been against men and in favor of women.

In my experience you learn much more about discrimination in tech by having open minded conversations than by seeing it firsthand. Much of it is subtle and happens out of view from others.