Who cares if they are all white 23yo frat bros? who cares if no woman can get hired so long as the company makes hires it likes. Or gay, or Jewish, or whatever busy is in your selection.

I'm not asserting there's a specific bias in this particular interview choice, but I am asserting that if you were taking a fairly narrow part of the population you better be working damned hard that you don't have hiring biases that are not relevant to job performance