alt Hacker Newsand yet ... that's not what the case you referenced says at all. Justia's own summary, from your link:
> Even if there is no discriminatory intent, an employer may not use a job requirement that functionally excludes members of a certain race if it has no relation to measuring performance of job duties. Testing or measuring procedures cannot be determinative in employment decisions unless they have some connection to the job.
(emphasis mine)
They worked at a power plant, a place where dumb mistakes can cause explosions and kill people. The power plant wasn't racist and hired blacks into the labor department, but because it was just manual labor that department paid worse than the other more technical departments.
When SCOTUS found against the power company they sent a clear message that merely being a technical, safety-critical job was an insufficient basis to establish a need to test people for intelligence. And as it's hard to argue that testing isn't needed for people who could cause massive power outages but is for <job X>, that was widely interpreted to ban such aptitude testing for any kind of job.