"Systemic" discrimination is rarely actual discrimination in the sense of illegal hiring practices. Women enter and graduate from college at higher rates than men. Thus it's "systemic discrimination" against men to require a college degree. But since it is valid to require education credentials to perform related jobs, nobody can sue for this. Almost every hiring practice is systemically discriminating at some level. If I'm hiring a Spanish to English translator, surely it's legal to ask applicants to translate a piece of text, right? But that's going to be heavily biased in favor of Latin Americans. Even the audition-behind-a-veil example is surely systemically biased in favor of people who had disposable income to hire musical instructors at a young age, and lots of free time to practice correct?

The requirements to prove a discrimination suit are far more direct: you need to prove that the company directly used protected class to make hiring or compensation decisions. And if the people making these decisions were never even informed of the candidate's protected class status it's exceptionally difficult to make the case that this was affecting this decision making.

> for example, basing a candidate's pay on 110% of their pay at their previous employer can result in implicit wage discrimination because men tend to enter the workforce at a higher pay and catch higher pay bumps in promotions

Actually, this is a perfect example of something that isn't going to get the company into legal trouble. They didn't make this decision on the basis of race, gender or another protected class. They made this decision based on something entirely objective: the candidate's previous pay. If that employee's previous employer was engaging in racial discrimination, then that's the company that vulnerable to a lawsuit.

I'm interested in this notion that you can sue your current employer, because a co-worker's past employer potentially engaged in gender discrimination that bumped their salary, which in turn was used in negotiations with the current employer. Do you have an example of any such lawsuit succeeding?