Employers used to have standardized tests for all sorts of things. The tests enabled a lot of upward mobility for people to pursue occupations that did not require college degree. If you could show aptitude in a test and had at least a high school education, they'd take you on and train you and you'd have a nice career.

However, certain groups sued saying that "equality of outcome" is more important than "equality of opportunity". They argued that if the outcome of a test showed intersectional differences, then the test must be biased. They succeeded in pressuring the various trade groups and industries to get rid of the tests or be sued into oblivion.

The trade groups that offered these tests realized it was just easier to require college degrees as a proxy instead of having their own specific tests and having to deal with these pressure groups. This is why many occupations these days require a degree when it seems like that should be unnecessary.

This slammed the door to upward mobility for many that the pressure groups were claiming to try to help.