Hiring someone in the off chance that their ethnicity gives them some unique critical unknown unknown that will pop up half a decade down the line resides in the same mental space as a programmer writing `if (5 == i)` in case a future programmer accidentally deletes an =. It's just speculative defensiveness whose efficacy is simply not well established by actual research. And, in my view, just works to confound actual signals that, evidently, gitlab and other employers feel get unfairly overshadowed when emphasizing explicitly pro-diversity hiring policies.