During the big push for this, I believe in the mid 70’s, it was represented as unnecessary because the constitution already expressed it. As we have seen since, some things need to be spelled out plainly before some people listen. I worked for Ma Bell, and she believed in equal pay. I worked a traditionally woman’s job (operator), and worked with women in traditionally male job (lineman/splicer), and while there was discrimination by some coworkers, I never saw any by the company.